Early indications from my poll on here and on Warseer point towards either a Crimson Fists or Deathwing campaign. Best for me to keep you informed of the ideas I have for each so that you can decide for yourself which direction you would like the hulk to go in. I've tried to come up with something characterful which will develop with time until I make the campaigns.
Crimson Fists - I could debut the extensive hive world campaign system which I have built and playtested, where the Crimson Fists have to eradicate a large Genestealer cult in a very populous hive. This campaign lends itself well to the experience system I have constructed and offers a branching storyline and multiplayer play. It's actually more rpg influenced and combines Space Hulk with other systems, like Necromunda or Mordheim. Don't worry though, you won't need either game to play as my new (and original) experience system add-on will give you everything you need. The good thing about this campaign is it was created to allow a sense of competition among players. Our original campaign used my vanilla terminators against some Blood Angels and the point of the campaign was to be the most destructive chapter. If this one wins, I'll want to pick a second chapter for the Crimson Fists to be competing with to bring down the stealers and allow for some butting of thick space marine heads.
Dark Angels - The Dark Angels are never more characterful than when they are hunting one of The Fallen. This campaign won't be set on a Space Hulk but on a fully operational cruiser. The cruiser has only one "human" occupant, a fallen in the thrall of the Chaos God Slaanesh. The action will follow a five man team lead by an interrogator chaplain, gunning through a ship filled with daemonettes to capture the shameful excuse for a Dark Angel hiding at it's core.
Grey Knights - Obviously more daemonic goodness here. Replace Slaanesh with Nurgle, add zombies in to the mix, set it during the Eye of Terror campaign and pack in a lot more danger to match the Grey Knights rather amped up abilities and we have lift off. Two missions were already written for this campaign as well as rules for Grey Knights in Space Hulk. There's also an interesting end of campaign boss I have in mind.
Ultramarines - The Terminators are usually the attackers in Space Hulk storylines, venturing deep in to hulks to destroy the menace within. At one point in the Ultramarines history, these tables were turned. On Macragge, during the invasion of Hive Fleet Behemoth, the polar fortresses were assaulted by a vast number of Genestealers. I want to recreate the defence of the tight corridors of the fortress that represented the Ultramarine 1st company's last stand.
Imperial Fists - The only Special Character driven campaign I will do, this campaign will involve Darnath Lysander and a couple of squads of Imperial Fists in a more standard Space Hulk campaign (except, obviously, for his inclusion.) Expect heavily adapted versions of the mission book missions to make them more balanced and/or difficult.
Space Wolves - My follow up campaign to the Ark of Dust which follows the surviving Space Wolves from that campaign on to their next hulk. They will be even more experienced and grizzled but with new squad members in tow. Gribbly hilarity ensues.
Blood Angels - This will be a series of short, unlinked missions which I will likely do anyway. In the vein of Suicide Mission, this will be a sort of coffee break space hulk, using one squad and no more than 20 tiles and 7 doors.
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