A new Forge World arises

Kataphrons

The big guys of the Cult Mechanicus are closer to tankettes than they are to people: their Ogryn-sized T5 frames make them difficult to remove from an objective, and with 3W your HQs can actually repair them. Their long ranged firepower doesn't suffer the penalty for moving; like a Russ tank group, they ARE the gunline wherever the enemy finds them. This comes at the penalty of advancing only d3"...which you don't really care much about: the only maneuvering they need is usually just to get a line of sight to the enemy. GREAT firepower coming from Troop units.

• It's worth noting that these puppies can be a huge fire magnet. A smart opponent will point medium weaponry at these guys and frankly, they're not quite as tough as they seem. Point efficiency and multiple wounds don't mean a lot when a punisher cannon can delete a 3 man squad in one round of shooting.
• To compensate, provide them with the Stygies VIII Dogma to increase their survivability considerably.
• Or take in units of 6 in Agripinaa to bring the full squad back from the dead if one model survives. With CP to burn this is horribly good on breachers.
• Or take as Ryza plasma destroyers hoping you'll play a knight list and can make your points back in one round of shooting accepting their won't be a second round.
• Or Lucius and deepstrike them in guaranteeing destroyers one round of fire.

• Kataphron Destroyers: Dedicated anti-MEQ gunships. As they trade a measure of protection (4+/6++) for amazing firepower, they will be a prime target for your enemy so they have to be defended.
  • Guns: Heavy Grav Cannons are reliable; Heavy 5 AP-3 deletes infantry, and D1d3 against anything with a 3+ save melts heavy infantry and can even dent monsters and tanks. Plasma Culverins today are just not so good. They have better 36" range But are more expensive , and Heavy d6 shots are unreliable. They only shine when supercharging, becoming able to deal with anything... but they also blow up on roll of 1. Now that's balance!
  • Sidearms: Their Phoshor Blasters are the budget option to use against targets of opportunity. However, Cognis Flamers give Destroyers protection against melee at mere +2pts. Bubblewrap units are still great, but with flamers their overwatch becomes nasty; their main guns already have enough RoF to proc overwatch hits and the stats for it to matter.
• Plasma culverins are high variance over grav cannons. Their D6 shots make them unreliable and absolutely undercut their usefulness over the grav cannons, even with their higher strength. (High variance can be both a strength and a weakness depending on how well you accept risk.) Anyone running plasma destroyers will need tons of re-rolls. Plasma is also 10 pts more, so with random shots and supercharge killing on 1 they are not what they used to be. Don't let the T5 with 3W and 4+ with shroudpsalm to get a 3+ fool you: these guys are glass cannons and prime targets for anything that mulches heavy infantry. Anything with decent strength or a point or two of AP will turn these guys into spare parts in one go if you don't do something to protect them, even with shroudpsalm. My personal advice is to abuse the [Acquisition at any cost] stratagem to get them to 2+/5++ saves on an objective and hope they can weather the storm with enough guns still intact to do their job, OR (and my personal favorite idea) consider running them as [Lucius], as the immunity to AP1 is absolutely fantastic on them (and its pretty solid overall) and the ability to pay a CP to hide a 6-9 man unit of kataphrons in deep strike is worth its weight in gold, as they have more than enough range to be confident that they can drop in somewhere they can hit their target, and you can even give your dominus the Lucius relic to teleport him to the kataphron gunline without losing his support for the footsloggers turn one, or paying the CP to deep strike him. Also, for 55 points you should always take Daedalosus, especially when you're taking these guys (they're only BS4+ after all).

• Kataphron Breachers: Trades some firepower for 3+ armour but, most importantly, at discount price. Enough to be heavy speedbumps yet disposable. Breachers bring 9W for 105pts and their Heavy Arc rifles (36" Heavy 2 S6 AP-1 D1d3) are not only basically anti-infantry autocannons, but also tear D1d6 chunks out of vehicles, so they can even help your overworked Onagers. And unlike Destroyers, Breachers aren't defenseless in combat, with three WS4+ attacks using Arc Claws (S6 AP-1 & D1d3 vs vehicles). With those stats, they are a screen by themselves. If you NEED an objective to be positively, absolutely defended, activate Acquisition at Any Cost and they'll be very difficult to remove, with 4A and a 2+/5++ save. (Alternate take if supported by vanguard S6 Ap-1 still wounds marines on 2's and a unit of 6 will kill 3.75 tac marines) their not gonna touch a dedicated melee unit but can still give a bad day to enemy troops or small characters) and now we have unlimited warlord traits prime hermeticon increases their melee output by 50%
  • Torsion Cannons are hard to defend. S8 AP-4 is nice but they cost a lot, are single-shot and D1d6 is somewhat unreliable. Likewise, Hydraulic Claws are like power fists...but with only AP-1 like Arc claws they will struggle to go through their targets' armour Sv, and Breachers aren't dedicated melee units, could throw one into maybe kill Vehicles and Monsters in melee.
  • Agripinaa breachers are really strong if you have a huge amount of CP as a 6 man squad can potentially bring 5 back from the dead and relocate if just one survives. Which considering their tankiness is quite possible. Do this a few times and count the firepower you've soaked.
    • The clue is in the name for these guys though; the above chap is absolutely correct in his analysis for the average game, but GW covers bases for more narrative games too: Fortifications & other Immobile units are auto-hit so when you need to breach through some Fortifications you have at least 9 S10 -1AP auto-hitting hydraulic claws vs the S6 of arcs, and that's 9 lots of 3+ rolls instead of iffy 5+.