Now that we have looked at what the Imperial Guard are and their strengths and weaknesses, let's take a look at each unit individually and see how they work with the army as a whole.
The Commander is the backbone of your Imperial Guard Infantry. They have a rule called "Voice of Command", which gives benefits to Astra Militarum Infantry Units. The benefits are as followed:
Fire On My Target!
Re-roll 1s To Hit in the Shooting Phase
Suggested for Battle Detachment Cadians, Plasma Guns, Melta Guns, Krak Grenade Launcher, any Heavy Weapon. This Order sells Cadia as one of the most powerful factions in the Imperial Guard. It gives them reroll of all failed hits if they remain stationary. This is your go-to Order if you are dedicated Cadia.
Bring It Down!
Re-roll 1s To Wound in the Shooting Phase
Suggested for Flamers, Frag Grenade Launcher, Lasguns, Lascannon/Missile Launcher firing on High Toughness targets.
First Rank Fire! Second Rank Fire!
Lasguns and Hot-shot Lasguns become Rapid Fire 2
Highly suggested for dedicated Lasgun Squads such as Conscripts or Infantry Squads with no upgrades. Also useful for Tempestus Scions with no Special Weapons.
Move! Move! Move!
Move and Advance in the Shooting Phase, cannot Shoot.
Suggested for getting an Infantry Squad to an objective quickly to secure it. One thing to remember about this order is that if you advanced during your Movement phase, you keep the same role you made when this Order is issued.
For the Emperor!
The ability to shoot even if you Advanced.
Suggested for squads that not only have Assault Weapons but also Rapid Fire weapons (such as Veterans with Shotguns and Plasma Guns).
Get Back in the Fight!
The ability to shoot even if you Fell Back
Suggested for any squad that had to Fall Back.
Fight during the Shooting Phase.
Suggested for Commanders or a large group of Conscripts stuck in Close Combat.
Burn Them Out! (Catachan)
Re-roll the number of Attacks for Flamers and Heavy Flamers. Also ignores cover bonus for the phase if a Flamer/Heavy Flamer targets a unit.
Extremely useful for Flamers/Heavy Flamer Special Weapon Squads, Veterans, or Command Squads.
Form Firing Squad! (Mordian)
Can target Characters with Rapid Fire weapons even if they are not the closest.
Useful for Veterans and Special Weapons Squads to assassinate problem Characters like Psyker characters as well as Buff characters such as Space Marine Captains and Chaos Lords.
Repel the Enemy! (Vostroya)
Can shoot at units within 1" of them in the Shooting Phase. Can only target the closest unit.
Useful for squads with Heavy or Special Weapons locked in close combat. In my opinion, its the least effective order as it ensures that your team is locked into close combat. This prevents other units from shooting at it. Very situational order overall.
Fire on my Command! (Valhallan)
Can shoot at enemy units engaged in close combat. Risk of hitting friendly units engaged as well.
Useful for Heavy Weapon Teams and Special Weapon Squads against Close Combat squads locked down with Conscripts or Ogryn.
Mount Up! (Armageddon)
Can shoot and then embark in a friendly transport.
Useful for Veterans and Special Weapon Squads near a Chimera or Taurx. Good hit and run order.
Company Commanders can give 2 Orders while Platoon Commanders can only give one. Personally, I like the Company Commanders more as they give you more of the same benefits as the Platoon Commander for only 10 points more. The difference is that the Platoon Commander is an Elite choice versus the Senior which is an HQ choice. If you are running a lot of Infantry Squads, then having 2-3 Senior Commanders is what I would recommend at least to get the most out of your Guardsman. Creed can fill the role of 2 Company Commanders with Kell nearby if you take a Cadian army that relies heavily on Infantry Squads. Taking a Platoon Commander to give an order exclusively to a Heavy Weapon Team, Veteran Squad, or Special Weapon Squad is definitely not a bad idea since they are so cheap and provides a valuable asset to that unit. The Tempestus Prime also falls in this category and is the only option Militarum Tempestus (Stormtroopers) have as the Platoon Commander cannot be named "Militarum Tempestus" as his <Regiment>. Giving him the Command Rod makes him give two orders and should be considered if you are having him run with more than one squad of Scions or Tempestus Command Squads.
The Orders give the Guardsman, Veterans, Tempestus Scions, and Conscripts (sorry Ogryn/Bullgryn, Ratlings, and Commissars, you don't get the benefits) some pretty nice surprises for your opponent. It also makes weapons like the Plasma Gun and Lascannon have a bit more impact with the ability to Re-Roll 1s for To Hit (for Supercharged shots) or To Wound (since high Toughness targets require a 3+). Each of these options are not bad options to pick from, but certain units benefit from a particular rule more than others. For example, Conscripts or dedicated Lasgun Infantry Squads will greatly benefit from "First Rank Fire! Second Rank Fire!" as all of them come with Lasguns and can fire an insane amount of shots. Even with the Guardsman's Ballistic Skill of 4+ and the Conscripts of 5+, you can turn statistics more in your favor. Even Tempestus Scions with Hot-Shot Lasguns at 9" can get a nice little surprise for your opponent. Heavy/Special Weapon Teams benefit more from either "Take Aim!" or "Bring it Down!" depending on the Special/Heavy Weapon and the target you are shooting at. Obviously you don't want "Take Aim!" with Flamers.
One thing to keep in mind with Orders now with Conscripts. They only work on a 4+. This means that Conscripts aren't as reliable to receive orders as an Infantry Squad, which doesn't require a dice roll to issue.
Tank Commanders have their own Orders they can give to one Leman Russ Battle Tank or Demolisher Battle Tank.
Can Move and Advance in the Shooting Phase, but cannot Shoot or Charge.
Useful for Seizing an objective or getting Linebreaker on the last turn thanks to Defenders of Humanity rule if they are part of a Spearhead Detachment.
Gunners, Kill on Sight!
Re-roll 1s in the Shooting Phase.
Good all around for when you really want to hit your target with your Tanks. Your go-to Default order.
Strike and Shroud!
Shoot and then use Smoke Launchers
Useful turn 1 for survival and end game to hold an objective that you have claimed.
Pound them to Dust! (Cadia)
Re-roll number of Attacks for Turrent mounted weapons.
Great for any Battle Tank that utilizes a random attack such as Battle Cannons and Demolisher Cannons. Also goes fantastic with the new Grinding Advance rule as well.
Get Around Behind Them! (Talaran)
Move an extra 6" during the Shooting phase and still count as not having moved above this.
Awesome little order to get your tank in a position for cover and still utilize Grinding Advance.
These guys not only can issue Orders, but also have a higher BS than their normal brethren. If you are fielding an Armored Column force comprised of mostly Leman Russ Tanks or even more than one Leman Russ in a regular list, its worthwhile to have at least one in your force. Some people are taking them exclusively over the regular Leman Russ tanks due to the high BS. As far as what I would kit them out with personally, I would recommend making the Tank Commander a Tank/Monster Hunter. Give them weapons like the Vanquisher Battle Cannon or Demolisher Cannon with Lascannon and Multi-Meltas. The higher BS means a greater chance to hit and with special characters like Pask that are BS 2+ and issue an extra order, it'll make them quite an effective Tank Hunter indeed.
The humble Infantry Squad is cheap as chips, can take a Heavy and/or Special Weapon, and can form up into an even bigger squad thanks to Combined Squads Strategm. The downside with these guys is that they have a lower toughness, save, and leadership than Space Marines. They also have the crappiest base weapon in the game, the Lasgun. Standing at a whopping Strength 3, Rapid Fire 1, at range 24", its not the greatest thing ever. But if you combine it with the above mentioned Orders and weight in numbers, it can hold its own surprisingly well. Also, thanks to the new and improved Wounds chart, Lasguns have a chance to hurt even the toughest of models, including Tanks! Close Combat wise, they are not designed to go head long into the breach. Again, Orders, Combat Doctrines like Catachan's Brutal Strength, and certain characters like the Ministorum Priest can help in this regard. Their Sergeant can also take a Power Weapon, which will help them somewhat in close combat.
There are a few things to keep in mind with Infantry Squads if you are a returning veteran of Warhammer 40k. If you take a Heavy Weapon, you can have them fire at a separate target. This means that taking them only for the bodies to soak up wounds for the Heavy Weapon Team isn't as viable as it once was. Remember, your Guardsman can split fire now. Utilize it! Don't discount never taking them in an Infantry Squad because of old rules. Also, units can consolidate into close combat once the combat is done. This can cause choke points to happen should you take too many Infantry Squads and not spread them out as the game goes on. The rules overall have changed for the better and in a big way.
Strategms also can make even a basic 10 man Infantry Squad surprisingly effective. Grenadiers, which is a one Command Point (CP) Strategm, allows for that 10 man Guardsman squad to throw all of their grenades at a target. Combine this with Orders plus their Doctrine and you have quite a surprise for your opponent that gets too close (10D6 Strength 3 shots with re-roll 1s To Hit is nothing to sneeze at!). Some armies have access to special Strategms like the Valhallan's "Send in the next wave!" that replenishes a unit like a Command Squad kitted with Special Weapons that was destroyed or Cadia's "Overlapping Fields of Fire" that gives a +1 bonus to hit versus a unit that was previously wounded successfully.
One thing to remember that may seem like a small point, but still something worthy to keep in mind. Guardsman, while they are weaker than Space Marines, can actually SAVE VERSUS BASIC WEAPONS! They are surprisingly more durable than they were in previous editions. It is entirely possible to save half the squad from bolter fire in the open. Just because your Guardsman are out in the open doesn't mean instant death for them. Don't be afraid to move them out of cover when necessary to secure an objective or tie up a unit to protect a more strategic asset like your tanks.
The former be-all-end-all for the Imperial Guard in 8th Edition. In my opinion, Conscripts are nice but I wouldn't build an ENTIRE army around them on Troops alone. On top of being just as expensive as Infantry Squads thanks to Chapter Approved, they do have some other drawbacks as well. They only have Lasguns, no access to Heavy or Special Weapons, no Sergeants, have a 5+ BS, Leadership of 4 (Meaning you MUST keep a Primaris Psyker around with Mental Fortress nearby to keep them from fleeing), Orders only happen on a 4+, and they are now a unit size of 30 max.
They are great at holding objectives if you have some support backing them like Primaris Psykers and Astropaths mentioned before. But a crafty opponent can make them not stick around by utilizing Snipers and other rules to specifically target Characters not close enough. This can be gotten around by utilizing the new Ogryn Bodyguards, which can soak up some of those shots on behalf of your Psyker. Its extra points that can be spent on other things like more Heavy/Special Weapons. But don't expect these guys to do much outside of securing that objective. Combat wise, they are worse than Infantry Squads, with one less WS and BS but the same Strength, Toughness, and Save. And now with orders only working 50% of the time and Infantry Squads having the ability to become bigger thanks to Combined Squads Strategem, they aren't as combat effective as they once were. Something to keep in mind when taking Conscripts in your list.
Leman Russ Battle Tank
The Leman Russ Battle Tank is now no longer two separate entries in the new Codex. Now, the Demolisher and its weapons are rolled neatly into one single entry. They can also score objectives in the same way as Infantry Squads thanks to the new Defenders of Humanity rule. This only works if they are part of a Spearhead Detachment though. Leman Russ Tanks now have a new added benefit in the form of Grinding Assault. This allows you to fire your Turrent weapon TWICE if you moved less than half of your movement. It also allows you to fire your Turrent weapon without penalty should you move. Combine that with certain Doctrines like Catachan's Brutal Strength. Cadia's Born Soldier, Vostroyan's Heirloom Weapons, or Armageddon's Industrial Efficiency and you have quite a beastly little tank. One other point to make mention of is how Emergency Cooling Vents work now versus in the Index. Instead of taking 6 Mortal Wounds for rolls of 1, you now take 1 Mortal Wound for each roll of 1! This makes Overcharging your Plasma Cannons well worth it on Leman Russ Tanks! Combine that with Techpriest Enginseers to heal those wounds back up to full and you have a beast of a machine. Possibly the best tank in the game to date in my opinion!
There are some downsides with Leman Russ Tanks. The first is that while they can boast an impressive armament, they only have a BS of 4+. Tank Commanders come with a 3+ while Pask is the big daddy coming in at a 2+! This means that even with certain Doctrines and Tank Orders, you can still not hit as often as a Predator would. Points wise, they can be a bit pricey when you add up the guns on top of the base Tank. However, this codex did drop the base cost of the Leman Russ versus what was in the Index. And finally, a charge into them can render them almost useless for a turn as they have no way of firing after Falling Back. Screen them with Infantry Squads to make the most out of their firepower.
Each Tank can be customized to deal with a particular problem that your army might face. Got waves of Poxwalkers coming for your lines? Grab a Punisher with 3 Heavy Bolters! What about those Grey Knight Paladins? Take an Executioner plasma cannon with two Plasma Cannons and a Lascannon! What about a Devestator Squad in cover? Take an Eradicator nova cannon to negate that bonus plus Plasma Cannons! Tanks and Monsterous Creatures giving you a problem? Blow them away with a Vanquisher Battle Cannon, a Lascannon, and two Multimeltas!
If the Company Commanders are the Hammer of the Imperial Guard, then the Commissars used to be the Anvil. They are designed to keep moral strong, even if it costs the life of a single Guardsman. Their Summary Execution rule means that Imperial Guard units that fail a Morale Test within 6" of them only lose one model but gets a re-roll. They also give the added benefit of using his Leadership instead of their own if he is nearby. The bonus to Leadership seems to be overlooked at times and is worth noting since a Sergeant only gives a Leadership of 7 versus a base Commissar's of 8. One point does go a long way. Lord Commissars are the HQ version coming in with a higher WS, BS, and Leadership. They can help out in Close Combat in a pinch if necessary. With the ability to take a Power Fist or Power Sword and be given a Plasma Pistol, they can dish out some punishment up close. The Emperor's Benediction, which is a Relic Bolt Pistol that is Pistol 3 at -1 AP and 2 Damage with the ability to target Characters even if they are not the closest, is a nice little addition to give to one of your Commissars. It allows them to pick off at weaker models like Librarians and other weaker Characters hiding behind units. Commissars aren't a mandatory pick like they once were due to the change in how Summary Execution works. The Commissar is worth a look at since it gives a boost to Leadership for Astra Militarum units nearby. Also remember this DOES NOT stack with the Regimental Banner from Command Squads that add +1 Leadership to this as it buffs the base units leadership, not your Commissar’s!
Command Squads may be small, but they can provide some interesting bonuses to your army. They can be a Special Weapons squad with a BS of 3+, be given a Medi-pack to bring back a fallen Special or Vox-caster Guardsman, and take a Regimental Standard that provides a Leadership buff to units nearby. They are also cheap in terms of points, but very small and can be easily picked out in a crowd of Infantry Squads. It is best to put these guys in cover and near a Company Commander to give orders to the various Infantry Squads in your army. They provide great fire support and should be used as such. Stick a few Plasma Guns on these guys, give them the various equipment, park them in some ruins, and give that support your Commander desperately needs! You can also make them into a dedicated Tank Hunting team by giving them all Melta Guns, rolling them up in a Taurox with a Platoon Commander, and drive around looking for that nice Tank that's been causing you trouble. Alternatively, if you are Catachan, you can give these guys Flamers and a Heavy Flamer to run alongside your Platoon Commander that packs along a mean punch!
Special Weapon Squad
Special Weapon Squads are a team of 6 Guardsman that have access to three Special Weapons and count as an Elite choice. Sadly, in the new Codex, Demolition Charges are no longer an option for them (or anywhere else in the book for that matter). There are some benefits from taking a small team like this. For example, they can fill a small Sniper Team role when you don't have access to Ratlings to secure an objective, have two Meltagun teams that can drop out of a Valkyrie to melt away that Tank or Monstrous Creature, or even have two squads of Flamer Squads to ride shotgun in a Chimera to burn some lightly armored enemy forces!
The downside of course is that they are just Guardsman that have Special Weapons, meaning that they are just as vulnerable as Guardsman but are smaller in number and more expensive points wise. I would definitely recommend taking a Dedicated Transport to increase their durability like a Chimera or a Valkyrie to effectively deliver them into combat at full strength. This does mean that they will die shortly after unleashing their cargo. Also, they cannot benefit from the Vox-caster as they don't have access to it. So in order to benefit from Orders, they have to have either a Platoon or Senior Commander nearby.
Veterans are an Elite choice that are effectively an Infantry Squad with a better BS, more access to Special Weapons, and the ability to take Shotguns and a Heavy Flamer. Veterans are a tad bit more expensive than Infantry Squads with the same durability. The best way to utilize Veterans is like the Special Weapon Squads and utilize the Dedicated Transport like a Chimera, Valkyrie, or Taurox. Kit them out with three Special Weapons that match what you are most concerned about going up against and maybe even take a Heavy Weapon like a Lascannon or Missile Launcher since you can still move and shoot with them with a small penalty. If you are running them in a Transport, its not a bad idea to outfit them with Shotguns since they are two shots a piece with a Strength buff if you are close enough. It is entirely possible to field an army of them with the Vanguard Detachment, but remember that they do not have Objective Secured like the Infantry Squads or Conscripts.
Hellhounds are one of the two Fast Attack options given in the new codex. Sadly, Rough Riders are only available in the Index and will not be discussed here. Hellhounds come with three options for Turrent guns: Inferno Cannon, Melta Cannon, and Devil Dog. Inferno Cannon is a long reaching flamer (16" to be exact) that is Heavy 2D6! Combine that with a Heavy Flamer and you can cook some lightly armored horde squads like Poxwalkers and Conscripts. The Melta Cannon is a solid shot Meltagun with a longer range (24"). Apparently, you can take a hull mounted Multi-Melta now as well, making this a solid anti-Tank option. The Devil Dog is a Flamer that wounds on a 2+ versus Infantry with a -3 AP, but requires it to be within 8". This is pretty useful versus high Toughness Infantry targets. Remember, these guys can benefit from Doctrines as they are part of a <Regiment>. The most obvious ones who benefit from this are the Catachans, who can re-roll one of the D6s for the number of attacks a Inferno Cannon or Devil Dog receives. However, the least obvious is the Armageddon Doctrine. Small arms fire from weapons like Autocannons and Heavy Bolters can cause quite a bit of a dent in Hellhounds. But thanks to the -1 AP becoming 0, it makes them quite a bit more durable. Cadia's Born Soldier Doctrine and Moria's Parade Drill may be a bit tricky to use since this thing wants to be mobile and most of their guns auto hit regardless.
The closest thing to Close Combat effectiveness the Guard will ever get, the Ogryn/Bullgryn are surprisingly tough as nails with an impressive amount of wounds to boot. Ogryn are the shooting brethren while the Bullgryn are the dedicated Close Combat version. Coming in at a whopping Strength and Toughness of 5 with 3 wounds a piece, the Ogryn can provide a nice little buffer between your Infantry Squads or Leman Russ Tanks. The Ogryn are the cheaper of the two with a Ripper Gun that provides a -1 AP in close combat. The gun itself shooting wise is pretty decent with it firing 3 shots at Strength 5. It has no AP and only 1 Damage however. While the Ogryn themselves are a somewhat decent shooting with better than average close combat support, the Bullgryn are the pure close combat beasts of the Imperial Guard. Coming in with either a 2+ armor save or a 4+ Invulnerable save and a Strength 7 Mace with -1 AP that deals 2 Damage swinging 3 times per Bullgryn, they can pack quite a mean punch! Also one minor thing of note for returning players, Ogryn/Bullgryn no longer need a Character like a Commissar to tell them to get in the transport. They learned how to do that on their own.
Ratlings are your dedicated Sniper force. Unlike Special Weapon Teams or Command Squads, Ratlings can be in unit sizes as big as 10 models with just as high of a BS as a Veteran. Ratlings do get the option of moving again after shooting, which is a nice way to duck behind a rock to avoid line of sight or get into cover. The downside of them is that they are pretty easy to wound with a measly Toughness of 2 and a t-shirt save of 6+. Cover does make it a 4+ since they have a rule that benefits from a bonus to cover. If you need some cheap Psykers or Buff characters to go away, then taking a unit of these or two probably wouldn't be a bad investment.
The Tempestus Scions are the new Stormtroopers, with heavier armor and a better BS than their Infantry Squad counterparts. These are basically the better version of Veterans but more expensive points wise and are Troop choices by default. They can take 2 Special Weapons for every 5 models in the unit, drop in from orbit onto the battlefield with an Air Drop, and don't count towards being a dedicated Detachment for an Imperial Guard regiment. Armed with Hot-Shot Lasguns, they can actually pack quite a punch against armored units like Space Marines with the -2 AP. However, they do suffer from some drawbacks. They cannot take Heavy Weapons such as Lascannons and Missile Launchers, can cost as much as two Infantry Squads fully kitted out, and only benefit from their own Doctrine if you take a separate detachment of them exclusively. Taking them as a dedicated Detachment may not be a bad idea since they all get an extra shot for every 6 that is rolled (this includes the Taurox Prime by the way). Taking a dedicated detachment of Militarum Tempestus is easier than you may think since all you need is a Tempestus Prime and a unit of Scions to make a small Patrol Detachment. The best way to utilize them is by making use of that Air Drop to take out an important target. Remember that since their range is 18" and you are required to be outside of 9", you won't be able to Rapid Fire with your Hot-Shot Lasguns. If you are going to utilize this technique, take 4 Plasma Guns instead with a Tempestus Prime to give "Take Aim!" to them. Otherwise, I would recommend running them in a Taurox Prime to get them where they need to be as well as give some badly needed firepower.
The Sentinel comes in two flavors: Armored and Scout. There are subtle differences between the two besides point cost. The Scout Sentinel doesn't have the option of taking a Plasma Cannon, has a lower Save and Toughness versus its Armored variant, and can get a free move before the game starts. They can be great fire platforms for some extra firepower that is a bit more durable than the Infantry Squads or Heavy Weapon Teams. They are slightly more expensive as a squad of three than a Hellhound is. But the trade off is that you get three Toughness 6 Heavy Weapons with 5 wounds each. Mix that in with some of the doctrines like Cadia's Born Soldiers and Catachan's Brutal Strength for those Heavy Flamers, they can be a great addition to your force and a good cheap way to get a Battalion Detachment. Also, with the Stratagem "Go! Recon!", you can use them to capture an objective by going an extra 2D6" at the cost of shooting and charging. And this is after you moved 8+D6" during the Movement Phase!
One of the newer artillery pieces to come out recently, the Manticore has a heavier payload than the Basilisk. With a Heavy 2D6 missile that is Strength 10 and -3 AP that does not need line of sight, its hard to pass up the Manticore. However, these missiles can only be fired 4 times per game once per turn, making their late game effectiveness not very great. The Manticore is slightly more expensive than the Basilisk due to the high powered missiles it fires each turn and don't come in squadrons. This means that one Manticore counts as one Heavy Support. But honestly, two should be all you need as these missiles can be quite deadly on their own. Definitely not a bad pick and works hand in hand with some of the doctrines like Cadia and Catachan especially.
The original artillery piece. The Basilisk is the long range gun platform that can probably reach out to the next table over with its 240" Earthshaker Cannon. Previously, they had a minimum range of 36", but this only applies if you are utilizing the Master of Ordinance for that re-roll of 1s. Now, for a mere 108 points, you can have a big gun that is Strength 9, Heavy D6 that rolls twice and picks the highest for the number of shots, and -3 AP that does not need line of sight to fire. The downside is that it is a bit weaker in terms of durability versus its Leman Russ counterpart. Also fantasic with Cadia and Catachan's doctrines. If you really want to throw that extra 6" on top of your insane 240" gun, Vostroya has you covered there.
Deathstrike Missile Launcher
The Deathstrike Missile Launcher is one of those fun tanks that can cause a world of hurt on someone. If it can fire. Once per game, it can fire a Heavy 3D6 missile that causes a Mortal Wound for every hit on a unit and dealing more mortal wounds to nearby units it hit with the initial. The downside is that it has to warm up first before it can fire, making it an obvious target through the course of the game. It can only fire on a dice roll of 8+, getting a bonus to the roll for every one of your turns it currently is. Meaning that it can only fire on Turn 2 on a dice roll of 6. If your rolls are bad enough, it won't fire at all! If you really REALLY want to give this a try, I'd recommend taking at least two of them to have a chance of firing. Catachan's Brutal Strength benefits from this little tank the most as it can reroll the number of shots it gets to cause those mortal wounds. A smart commander will target the Deathstrike first thing. Even if it isn't killed, the lower BS as a result of the damage it takes makes its effectiveness far less when it actually does fire. Buyer beware with this missile of doom.
This is the newest artillery piece available for the Imperial Guard, replacing the Griffon. The Wyvern comes with a cannon that is Heavy 4D6 Strength 4 with no AP that can reroll failed wounds. This little artillery piece has been preferred in most armies simply because of its ability to reroll failed wounds and the amount of shots it gets. Despite it having a slightly less point cost than a Basilisk and the ability to take up to three as one Heavy Support choice, there are some drawbacks. The first is that if it fires against something with a high Save, its likely that these shots will just simply bounce off given it has no AP value and doesn't ignore cover. Its great for horde based armies to weed out those units, but for units with a bit more armor, I'd say bring a Basilisk or a Manticore instead.
Baneblade and Sons
The Baneblade. What's to say about this thing? Its a giant tank with a ton of really powerful guns on it! Each of the variants has their own powerful main gun. Some weaker than others and even one causing a debuff. Two can transport infantry units inside and have firing ports for them to shoot out of. No matter which variant you look at, they are the Imperial Guard's Lord of War choice. Chances are you are only going to field one of these things if you do. Any more than that and you'd be looking at the 3 Lord of War Detachment so that you can get the Doctrine. Clocking in at at least 500 points, these things are not cheap. But what do you get with something that would cost you the equivalent of 3 Leman Russ Battle Tanks? You get a 26 wound Tank that can have up to 5 Twin Heavy Bolters (for a whopping 30 Heavy Bolter shots from one Tank!), 4 Lascannons, sometimes a Demolisher Cannon, and the main gun. The main guns varies from a standard Baneblade Cannon that fires 2D6 shots at Strength 9 -2 AP that deals D3 Damage to a Strength 10 -3 AP cannon that fires 3D6 shots but has the same range as a Heavy Bolter. One of these main guns can deal an impressive 2D6 Damage (yes, Damage), and gives a bonus to hit Titans! The least impressive of these main guns is the Vulcan Mega Bolter that fires 20 shots at Strength 6 with a -1 AP that deals 2 Damage. The trade off is that it can transport 40 Infantry models and has space for 20 of them to fire out of it (Mortar teams anyone? How about 15 Flamers and 5 Heavy Flamers?). These tanks are powerful, but they have a BS of 4+ and a Save of 3+. Enough Lascannons and Missile Launchers can take it down in a short amount of work if enough firepower is directed at it. Its fun to run one of these monstrosities, but don't expect it to run over entire armies with it.
The Valkyrie is the Imperial Guard Flyer. It can transport 12 models, moves incredibly fast (over 20" at least), can boast an impressive amount of light fire support, and can drop Infantry at amazingly fast speeds (even as soon as Turn 1!). It can also be tough to hit thanks to the Supersonic rule that gives a -1 To Hit and could slow down to get a bonus of +1 To Hit ground troops. The Valkyrie also can be cheaper than a Leman Russ. The downside is that it cannot hold objectives by itself in Matched Play, its heavy weapons options versus heavily armored units are limited, and has the potential to have all of your troops die if shot down. Its a great way to get some Veterans with Plasma or Melta guns up close as soon as Turn 1. Note that the Valkyrie doesn't benefit from any of the Doctrines as it doesn't have the <Regiment> Keyword. However, if you have an Officer of the Fleet, you can give it a reroll of 1s To Hit units without the Fly Keyword. Personally, I would go with the anti-troop option as far as its weapons go because of the sheer amount of them you can get (Multilaser, Two Rocket Pods, and Two Heavy Bolters) versus the anti-tank variant (Lascannon and Hellfire Missile).
Hydras are the answer to opposing Flyers. Clocking in with a gun that fires 8 Strength 7, AP -1 dealing 2 Damage, the Hydra can plug a Flyer or two. It also gets a +1 To Hit bonus versus Flying units (so this counts towards Assault Marines or even Tau Crisis Suits, not just Helldrakes and Voidbombers). On top of that, they are fairly cheap in points cost. The downside is that they take a penalty To Hit if they fire on something that doesn't Fly, making them hit on a 5+ instead of a 4+. Its good to have one or two of these in your toolkit if you run into a ton of units that Fly. Remember that Jump Pack Marines, Daemons with Wings, and even Crisis Suits have Fly. So be on the lookout for units like this to take advantage of this tank.
Chimeras are the original metal box for the Imperial Guard. Able to transport 12 Infantry models and boasts a higher Toughness than the newer Taurox, its a good sturdy transport for getting squads to the battle safely. The Chimera also comes with a few turret gun options such as Heavy Flamer, Heavy Bolter, or the Multi-Laser. Personally, I like to outfit it with two Heavy Bolters or two Heavy Flamers as it does have a -1 AP value while the Multi-Laser doesn't. The Multi-Laser does have a higher Strength, but it only is beneficial if you are firing at Toughness 6 targets. Anything higher and you are still wounding on a 5+ regardless of which gun you take. You may as well get the -1 AP out of it. It also comes with a Lasgun Array that can only be fired if Infantry is transported in it. Its basically a Lasgun set that fires 6 of them at once, making a potential 12 Lasgun shots if its close enough. The downside with the Chimera versus the Taurox is that it moves slower than the Taurox and is more expensive point wise because of the Toughness factor.
The Taurox is the newer brethren of the Transport family of the Imperial Guard. It is cheaper than the Chimera, has two Autocannons, and can also move slightly faster. The downside is that it does have a lower Toughness and Wounds than the Chimera. For a transport, its not a bad option to replace the Chimera for basic troops like Infantry Squads. The Autocannons are slightly better for certain units that have multiple wounds like Primaris Space Marines and Death Guard that have a chance to negate damage. The Taurox Prime has far more gun options and are considered baby Leman Russ Battle Tanks. It can take a weaker version of the Battle Cannon or Punisher Gatling Cannon. The best option in my opinion is the rocket launcher that is very much like a twin Missile Launcher. The drawback with this transport variant is that the only infantry it can transport is Militarum Tempestus or Commissars and it is far more expensive than the Taurox because of the gun options.
Astropath/Primaris Psyker/Wyrdvane Psykers
The Psykers of the Imperial Guard are primarily used to buff your own units and debuff enemy units. They are not designed to be stuck into Close Combat. However, some of these Psykers are better than others. The Wyrdvane Psykers are only useful for certain spells that require a Warp Charge value of 6 or lower like Mental Fortitude and Nightshroud. The downside is that they are a unit that can easily be gunned down as their Save is only a 6+ and the effect of their casting goes down as they lose models in the unit. They can only roll one dice to manifest a psychic power. The Astropath is an Elite Character that can manifest spells normally and is only 30 points (formerly 15 but updated due to Chapter Approved). However, he is still a great supporting Psyker and is pretty dirt cheap for a buff to a unit's Save or a penalty of -1 To Hit a unit. The Primaris Psyker, like the Astropath, is also a great choice and counts as a HQ unit.
Master of Ordinance
Out of all the characters, the Master of Ordinance is the least favorite in the lineup in my opinion. This officer can call down a once per game artillery strike and give Basilisks, Wyverns, Deathstrike Missile Launchers, and Manticores a reroll of 1 To Hit if the target is over 36". The reason I'm not too fond of the Master of Ordinance is that in most games that are played on a 6' x 4' board, you are not going to be utilizing the rerolls too often unless you are going up against an opponent that has some artillery pieces parked somewhere like a Thunderfire Cannon. The artillery strike is essentially a free Basilisk shot once per game, which is alright for the points and really the main reason I would take him since it hits on a 3+ due to his BS. If you have some artillery tanks, its not a bad filler for the Elite slot. Otherwise, I'd pass on him personally.
Officer of the Fleet
The Officer of the Fleet is an Elite Character that helps Valkyries by giving a re-roll of 1s To Hit versus non-Fly units. Unlike the Master of Ordinance, there is no restriction on this other than the fact that it has to be within 18" of the Officer. Also, the Officer can call in a Air Raid that has a chance to do Mortal Wounds once per battle. However, multiple Officers can call in multiple Air Raids once per turn for the number of Officers you have. If you are running at least one Valkyrie, its worth taking this guy as he's only 25 points and is the only buff option the Valkyrie has.
A challenge worthy of his skill, the Tech-Priest Enginseer should be mandatory if you are running at least one Tank. Coming in at a whopping 42 points, this little guy from <Forge World> can keep your Leman Russes, Baneblades, and transports operating at peek efficiency. At the end of the Movement Phase, you can pick a Astra Militarum Vehicle within range to heal it D3 wounds. This may not seem like much, but it can be the difference between hitting on 5+ and 6+. It can also be combined with Jury Rigged, which can heal the tank for an extra wound so long as it doesn't move. Being that this little guy is a Character, he's safe to run beside a Leman Russ since it has to be the closest to pick out. Or park him behind a Tank to block line of sight for extra protection versus sniper fire. And he's pretty decent in close combat too being that he hits at Strength 5 with a -1 AP dealing 2 Damage. The Servo Arm gets one swing on its own at Strength 8 with a -2 AP that deals 3 Damage. Sadly, he hits on 4+ and only has two attacks. The Servo Arm hits on a 5+ though. But still, he is definitely worth taking for the repairs alone.
Heavy Weapon Squad
The humble Heavy Weapon Squads. These were almost required in previous army lists due to the fact that you couldn't split fire from Infantry Squads. But now that Heavy Weapons can indeed target a Land Raider without forcing the rest of his Guardsman to fire at it as well makes taking them as part of an Infantry Squad much more viable and almost required now. Costing as much as a Guardsman plus the Heavy Weapon in question, these guys come in packs of 3 on their own without their Lasgun wielding brethren as a Heavy Support choice. Compared to some of the other options in the Heavy Support category, these are the cheapest option, even with Lascannons. Personally, I'm not as much of a fan of them as I used to be though since they can be picked out quite easily even if they are benefiting from cover. That cover only gives a 4+ armor save and 2 Damage weapons can rip through these guys pretty quickly. I do, however, like taking them as a Mortar Team since the entire squad of Mortars benefits from 3D6 shots rerolling 1s (To Hit or To Wound) with an order from a Platoon Commander. Park them out of sight and go nuts! Even if the squad gets wiped out, you only lost 33 points. Not a bad investment that can get you Brigaide quickly eh? Just remember they also have Lasguns too. Its easy to forget that.