A lesser known Forgeworld Dreadnought variant is the Siege Dreadnought.
Weighing in at the cost of 24 MBs a piece and with standard “old-school” Dread stats (i.e. WS4 BS4 S6 F12 S12 R10 I4 A2 HP3), this walker comes with some unique and potent wargear:
1 – Flamestorm Cannon — Same weapon that is on the LR Redeemer, being a S6 AP3 Template weapon.
2 – Assault Drill with Built-in Heavy Flamer — Assault Drill is a Power Fist that gains an additional D6 for Armor Penetration against buildings and stationary vehicles. Additionally, whenever it causes at least one Penetrating Hit on a tranport/building, then every embarked model takes a S5 AP4 hit.
Like other Dreads, the Siege Dread can Drop Pod in, allowing it to get up close with your enemy turn 1 and unleash both its templates. This provides tremendous utility to any Marine force or even another force that takes and Astartes ally. Some examples of lucrative targets for a Siege Dread “drive-by flaming” are as follows:
1 – Necron Warrior/Flayed Ones phalanxes — With the ability to drop in and release two templates with AP4 or better and ignoring cover, the Ironclad Dread can deal masssive casualties to tightly packed Necrontyr, even enough to overcome 4+ Reanimation Protocals from Decurion/Cryptek buffs.
2 – Eldar Jetbikes — With the Flamestorm ignoring both their armor and cover saves and wounding on 2+s, this is a great way to hunt down small-medium jetbikes squads with massed Scatter Lasers and take out massive chunks of Eldar S6 shooting before the end of Turn 1.
3 – Ork Loota Boyz/Flash Gitz in Cover — A great way to “napalm strike” Ork fire-base units in a single turn and greatly reduce the synergy of their army, making them much more mono-dimensional (i.e. close combat focused only).
4 – Tyranid hordes with Venomthrope support — Ignoring cover and AP3/4 means that basically every Gaunt/Hormaguant/Ripper etc hit is a dead beasty and is a great way to clean out hordes supporting Tyrranid “monster mash” lists.
5 – AM Blob Squads behind Aegis Defense Lines — With the “Get Back in the Fight” order, AM Blobs can go to ground each turn and get a 2+ cover save, then “recover” next turn and shoot again with basically no penalty. The antidote to 2+ cover saves is, naturally, multiple Ignore Cover templates coming out of a Drop Pod turn 1, especially against tightly packed AM infantry.
6 – Tau Pathfinder Teams/Markerlight Drone Squadrons — These guys almost always deploy in cover to maximize their survivability and abiliy to employ Marker Lights. Dropping in turn 1 and hitting them with two S5/6 AP4/3 templates can kill an entire Pathfinder Team or Drone Squadron in a single volley, in turn dramatically reducing the overall combat power of a Tau army.
7 – Dark Eldar Skimmers/Embarked troops — With S5/6 templates shooting against Open-Topped transports like the Venom and Raider, the Siege Dread can potentially kill the DE vehicles outright or, at the very least, inflict 2D6 Heavy Flamer/Flamestorm hits on the occupants, which should be enough to devastate pretty much any DE passengers outside of maxed out Grotesques.
8 – Skitarri Infantry of all kinds — With only a 4+ save, T3, and no access to transports, the Skitarri are particularly vulnerable to the S6 Flamestorm template, which ignores their FNP and also causes ID to Ruststalkers and Infilitrators. Even Ironstriders and Sydonian Dragoons can be damaged by the S6 templates, since they are only AV11 and open-topped.
9 – Power Armor Infantry of all varieties (i.e. Wolves, Blood/Dark Angels, Grey Knights, “normal” Space Marines, CSM, even Sisters of Battle) — As long as they are not in a transport or building, these units are quite vulnerable to Siege Dreadnoughts and their Flamestorm shooting, not to mention follow-up attacks by the Dreadnought if it survives long-enough to charge into close combat on turn 2.
In summary, basically the only units that are “safe” against a Siege Dreadnought turn 1 drop are medium/heavy vehicles, Monstrous Creatures, infantry with a 2+ save (or very high Invul save), and flyers/FMCs. This means that Siege Dreads have very strong viability in any TAC list, either as part of a base-line Astartes force or as an Ally to another army.