Space Marine Review: Heavy Support- Thunderfire Cannon

Hi everyone, Michael here with a review of the Thunderfire Cannon, a great support weapon for the Adeptus Astartes. For more reviews and analyses, check out the Tactics Corner.

The Thunderfire Cannon is a Heavy Support choice for the Space Marines. The unit consists of a Thunderfire Cannon and Techmarine Gunner, coming in at a bargain 93 pts for the unit.

The Thunderfire Cannon is most definitely a Competitive choice. It is common to see at least one, if not more, of these in a tournament Space Marine list. It provides some fantastic long range anti-infantry firepower that can fire at units out of line of sight. It also has access to a couple of very strong stratagems that further boost its utility.


  • Thunderfire Cannon- 60″, Heavy 4D3, S5, AP-1, 1 damage. This weapon can target units that are not visible to the bearer.
  • Techmarine Gunner has Flamer, Bolt Pistol, Plasma Cutter and two Servo-arms


  • Angel of Death
  • Operated Artillery- At the start of any phase, each Techmarine Gunner can operate one Thunderfire Cannon within 3″ of it. Each Gunner can only operate one Cannon each turn.
  • Crewed Artillery- After set up, this unit is divided into two separate units. If there is no Techmarine Gunner within 6″ of the Thunderfire Cannon, the Cannon is destroyed.
  • Blessing of the Omnissiah- At the end of your movement phase, the Techmarine Gunner can repair one friendly <Chapter> vehicle within 1″. The model regains D3 lost wounds.


The Thunderfire Cannon is a great long-ranged support weapon for a Space Marine army. The range of 60″ means that it can target almost any unit on the battlefield with a central deployment. This provides the Thunderfire Cannon with a huge threat range, so can contribute its firepower to the battle for every turn that it is functional in most cases .

The Thunderfire Cannon gained a number of benefits in the new codex. The first is it went up to BS2+, which is a great boost to its accuracy. In addition, it also went up to a 2+ armour save, further improving its durability.

The Cannon has the potential to do between 4-12 shots with one volley, averaging about 8 shots per turn. At S5, it will be wounding most infantry units on a 3+, making it great for taking on weakly armoured infantry, such as Ork Boyz or Guardsmen. On the first turn, with the Devastator Doctrine active, the Thunderfire Cannon will be at AP-2, so will be great for taking one more heavily-armoured infantry or those in cover. It will still be AP-1 if you switch Doctrines, so will be useful for taking on a variety of units after that.

The Techmarine Gunner has some decent firepower with the Flamer and Plasma Cutter, but you generally won’t be getting to use these unless your opponent gets really close. Ideally, you won’t want to have to use his firepower, as you want to keep enemy units away from your Cannons.

The Thunderfire Cannon has some decent defence against enemy attacks. At T6, four wounds and a 2+ save, it will take some reasonable firepower to destroy it. However, its best defence is that fact that it does not need line of sight to fire, so you can afford to hide it behind some ruins or in cover, out of sight of the enemy firepower. It will only have to worry about your opponent’s indirect fire in most cases. Another bonus of the Techmarine Gunner is the ability to heal D3 wounds per turn, so you can heal up the Cannon if it takes damage during your turn but is not destroyed.

The Thunderfire Cannon is great for taking on enemy units that are holding backfield objectives, potentially hiding out of line of sight or inside a magic box. This also makes it useful for taking out weaker Engineer units that are hiding out of line of sight, stopping your opponent from scoring these points. I also find the Cannon is great for targeting weaker enemy units for scoring First Strike or First Blood. It is great for taking out squads such as Space Marine Scouts, small units of Grots, Astra Militarum Infantry Squads, etc. This can be a nice, easy way to pick up a kill point or First Strike with relative ease.

The Cannon also has access to a couple of great stratagems. The first is Suppression Fire for 2CP. This allows you to fire the Thunderfire Cannon again if it did not move. This doubles the firepower available and can be great if you are only running a single Thunderfire Cannon and need to finish off a key enemy unit in your shooting phase, or if you have a bad roll for the number of shots with your first volley. It is pricey at 2CP, but it has come in very useful for me in a variety of tournament games for ensuring that I score a point or take out a key enemy unit to stop my opponent from scoring.

You are less likely to use this if you are running multiple Thunderfire Cannons, but could potentially allow you to fire up to 4 times with three Cannons, and do a lot of damage to enemy units.

The other useful stratagem is Tremor Shells, for 1CP, If you use this, you subtract one from the wound rolls. However, if you hit, then the unit that is targeted must halve their movement, advance and charge rolls in their turn (unless they have the Fly or Titanic keywords). This gives you the ability to seriously hinder the movement of a key enemy unit, or stymie an attacking charge in your opponent’s turn. I don’t find that I use this stratagem all too often (I don’t think I have used it in any of my last 10 tournament games), as many of the units you might want to stop have the Fly keyword. However, I think it has the potential to be game winning in many situations.

In a game that places a lot of emphasis on moving and grabbing objectives, the ability to restrict your opponent’s moves and deny them a charge or objective-grabbing move is a great tool to have at your disposal. When paired with the great board control units the Marines have access to (Scouts and Infiltrators), this can really allow you to restrict your opponent’s moves.

As far as I am aware, you can pair Tremor Shells and Suppression Fire on a single cannon. For 3CP, this allows you to halve the movement of two key enemy units in your turn, a great bonus if you get the first turn. I’ve used this to great effect to restrict the movement of a couple of Lord Discordants or large mobs of Ork Boyz, keeping them from being a big threat to your army for several turns for a reasonable CP output.

Support Units

A Captain or Lieutenant are great support units for a Thunderfire Cannon, allowing you to re-roll 1’s to hit and to wound, respectively. This will help to boost the damage output of your Thunderfire Cannon(s) in the shooting phase.

It can also help to have a screening unit for the Cannon to prevent enemy reserves from getting close enough to target the Thunderfire. A unit of Devastators or Intercessors can perform this role, as well as giving you a unit for holding an objective, as well as contributing their firepower to the army.

Chapter Tactics

Iron Hands is obviously a strong Chapter Tactic for the Thunderfire Cannon. This allows you to re-roll 1’s to hit while the Devastator Doctrine is active. Not only does this improve the accuracy of the Cannon, reducing the need for Captain support, but your Thunderfire Cannon will likely be at AP-2 for the whole game, boosting its damage potential further (unless you change Doctrine for some reason). In addition, you get a 6+ save against wounds, giving you a nice durability boost to the unit.

While White Scars is not a great Chapter Tactic for the Cannon, it does give you access to the Feinting Withdrawl stratagem. This allows the unit to fall back and still shoot, useful if your Cannon does get tagged in combat but is not destroyed.

The Ultramarines Chapter Tactic also allows the unit to fall back and fire, at -1 to hit. While the Tactical Doctrine is active, you can also move and fire without penalty. Less likely to be use, as you probably don’t want to move the cannon far from its starting position, but may be useful every once in a while.

Imperial Fists allows you to ignore cover save bonuses on the Cannon. This is very useful, as you are likely to be targeting units in cover or behind cover with the Cannon during many games. With AP-2 and ignoring cover, this can put the hurt on a number of enemy units in the first turn, and subsequent turns. The bonus to damage against Vehicles is only a good bonus if you happen to need to target a vehicle, or are attacking lighter vehicles, such as Venoms or Sentinels.

If you are making your own Chapter, then Master Artisans is a great boost for the Cannon. The ability to re-roll a single hit and wound roll is great for boosting the damage capacity of the Thunderfire Cannon.


The Thunderfire Cannon is an incredible fire support unit for the Space Marine army. At only 93 pts, it is an absolute bargain, and it is common to see several cannons in a competitive army. It is able to function without character support in many cases (especially as Iron Hands), and its ability to provide indirect fire is great for a variety of situations.

It has some reasonable durability to enemy fire, especially if they lack any form of indirect fire themselves.

The Thunderfire Cannon is great for targeting a range of enemy units, but works really well for weak infantry squads, where its S5 can have most effect. It also has access to a couple of key stratagems, including the potentially game winning Tremor Shells. It is well worth the inclusion in any Space Marine army.

And remember, Frontline Gaming sells gaming products at a discount, every day in their webcart!



About Michael Corr

An avid 40k player and blogger from Scotland. I started in 3rd edition and have been playing ever since. I detail my adventures in my own blog "St Andrews Wargaming", highlighting my mediocre painting skills, regular battle reports and my occasional random ramblings.

10 Responses to “Space Marine Review: Heavy Support- Thunderfire Cannon”

  1. Kurt December 31, 2019 10:31 am #

    “The Thunderfire Cannon is an incredible fire support unit for the Space Marine army. At only 93 pts, it is an absolute bargain, and it is common to see several cannons in a competitive army. It is able to function without character support in many cases (especially as Iron Hands), and its ability to provide indirect fire is great for a variety of situations.”

    That’s more like this:

    “The Thunderfire Cannon is an overpowered 60″ No LoS shooting units for the Space Marine army. At mere 93 pts it’s an absolute braindead choice, and practically every Space Marine includes several cannons for both it’s ludicrous firepower (thanks to overpowered Chapter Tactics, Doctrines AND Super-Doctrines) and the braindead option to COMPLETELY shut down units at will without retaliation at all (be it thanks to no LoS AND 60″, fuck you other armies that aren’t Space Marines), such is the game design of Games Workshop!”

    • Michael Corr December 31, 2019 3:25 pm #

      Not a fan then?

      • Jace December 31, 2019 4:32 pm #


  2. Dakkath December 31, 2019 11:20 pm #

    Operated Artillery- At the start of any phase, each Techmarine Gunner can fire on Thunderfire Cannon within 3″ of it. Each Gunner can only operate one Cannon each turn.

    I hope that’s a typo, because being able to shoot those things with tremor shell in your opponent’s turn is just crazy scary.

    • Michael Corr January 1, 2020 3:52 am #

      Yeah, bit of a typo there! That would be a bit ridiculous. Fixed it above.

  3. Rob Butcher January 1, 2020 11:46 pm #

    I got a Thunderfire cannon three years ago after reading Reece’s comments about his army list. They are a great, cheap source of firepower for my Imperial Fists. “Tremor shells” has been tactically used to deprive opponents the speed to reach objectives in early turns and to stop potential charges in later turns. I’m still waiting for some-one to charge my TfC …

    The main limiting factor to “Suppression Fire” is having to be out of line of sight for that second shot. That has been limiting on some boards with poor terrain.

    BUT it’s been useful for counter-battery fire — hitting the opponents own OLoS units like dark reapers, mortars, eliminators etc.

    The main question is how many to take? 2 for redundancy or 3 for cheapness. 1 is easy to hide on most boards. 3 can be more challenging on many.

  4. Michael Corr January 2, 2020 5:18 am #

    The Thunderfire Cannon does not need to be out of line of sight to use Suppression Fire. It can do so in line of sight, but can only fire weapons that do not require line of sight.
    This distinction is more for the Whirlwind, so it can’t fire attached Storm Bolters multiple times.

    I tend to find one is good for me. It rarely gets targeted and usually survives the game.

  5. Rathstar January 6, 2020 4:23 am #

    The mortar is now balanced, long live the undercosted thunderfire cannon 🙂

    In an army with many undercosted units, its just doesn’t stick out from the crowd.

  6. Sergio February 11, 2020 5:04 am #

    Could you please explain how you targeted Lord discordant with TF Cannons since they have the Character keyword?

    • Michael Corr July 9, 2020 7:38 am #

      They are over 10 wounds, so can be targeted despite the Character keyword.

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