Anyone got any suggestions on how to man an Imperator Titan, and battle with it?

I was thinking of using the general Starship Combat Mechanics, modified to a smaller scale.
Example, the pilot performs maneuvers, the crew makes shooting or extended actions, except each round represents a much smaller amount of time - maybe 5 seconds like normal combat, or 10-15 seconds to simulate the colossal scale.

Depends on how you're looking at using it. That bad boy has shields that compare favourably to starship shields, mounts a defence laster - effectively a lance - on a mount allowing it to shoot into orbit and its main weapon was originally designed to be mounted as a macrocannon option. So you could probably duel one with a ship - hell, it'd probably win against a transport.

In game? You could use titans with ship combat, but if a Warhound is a Frigate, a Reaver is a Light Cruiser, and a Warlord is a Cruiser, the Imperator currently has no viable equivalents in ship terms. Entire battle groups of Engines are required to fight even one, and it will comfortably kill anything that is slightly under Imperator size in seconds.

Your best bet for using one might be as a bit of terrain - a setting for a combat, rather than a vehicle for it.

Well it's not going to be used against ships, but rather a Greater Daemon of Tzeentch.

Even if there's no real equivalent, I still need to come up with some combat specs for its weaponry, and how the players can use it.

I guess it will essentially have to be a terrain piece then, where the players have to solve problems throughout it that arise during the fight? It is an ancient titan that been buried for many many years after all, and there could be several malfunctions...

Have a look at the orbital bombardment rules in Battlefleet Koronus , on the groundsthat firing the main weapons will be roughly similar for any poor bastards within a few kilometres of the target. Or Atomics - that would probably count for the plasma weapon

Please don't be offended, but I laughed when I read this. If the Imperator Titan is the larger end of the spectrum, the one that looks like a cathedral on legs, whose feet are large enough to transport troops and tanks (that'll teach ya to try and close with it ), then stats become irrelevant; even a Greater Daemon/Daemon Prince of Tzeentch, my favorite Ruinous Power, cannot do anything but commit suicide at the sight of it. The Imperator is a Heavy Titan, when compared to "regular" Battle Titans, much as a Baneblade makes a Lemun Russ look toy-like, and around 400 feet tall, so no one enemy of lesser scale (and plenty of on-foot soldiers can gak a Daemon Prince, with some casualties) could hope to tackle it. With void shields, it's as safe as a starship, and its Hellstorm Cannon would one-shot that fallen Marine, no matter what, unless it just plain missed (I assume at that scale, hitting such a "little" target gets tricky).

Okay, let me step back. I am not trying to be a ****** here, so lets see... Well, first, your party may have a bit to worry about. A Titan of any class can only be operated by a Princeps, the Collegia Titanicus's rep who can do this stunt. Without being sure what all upgrades the pilot might need (I don't know if they must be a full Tech-Priest), I do know that they need an MIU (Mind-Link Interface Unit?) to connect to the Titan's machine-spirit, and a strong enough Willpower to dominate it, so that it will do as they command. Other people, usually the Moderati, monitor systems, see to weapons, regulate power, etc, and a Tech-Priest assists. If your party can get past that, or if they find a Titan intact, with crew, then they should be good. Once we get around making it work, the Titan's weapons should be more than enough to deal with anything on the ground. Imperators don't have melee weapons beyond stompy feet, ever, but their guns, ranging from Volcano Cannons, or Melta Cannons, to Apocalypse Missile Launchers and Plasma Annihilators will take on all comers, and the void shields will keep any enemy at bay. Deathwatch: Rites of Battle, p.186 has the stats for a Warhound Titan, the Lupus Tempestus. If you have said book, or can get a copy in hand, that could be a nice place to start, and then just ramp it up. Rules for its Plasma Blastgun, Vulcan Mega-bolter, double-barreled Turbo-Laser Destructor, and Inferno Gun are included. However, even at this scale, redundant void shields will make for a difficult assault, and its weapons are expectedly ridiculous, doing from 30 to 50 damage a shot, with Pen that ignores anything besides a field, with silly range, and nigh-infinite clips. A single anything, even a Daemon Prince, should not have to fight one of these, and would likely need a HUGE horde of something sick to protect it. If they do, go heavy on the malfunctions, or something, or the encounter will read like the "Ascended Psyker killed 3 Greater Daemons in One Turn" thread. DW Greater Daemons might squeak out 150+ Wounds, but the best Daemon Princes probably won't, so he'll need to be very careful.

venkelos said:

Like anything, a possessed Chaos Impeartor Titan is somehtign to recon with even for a loyalits one...

The Lord of change I'll just teleport itself inside the cockpit and change hem all to is wishes.

At that point, I'd have to rule that such a war machine sports a Geller Field (even if its DW write-up mentions no such thing; anything big enough to mount redundant void shields should be able to carry one. Otherwise, if it was as easy as you say, the Imperium would have stopped using Titans, beyond the AI one from eons past, that made a pact with Chaos, and could even launch daemons out of a cannon it sported. Somehow, every tank, superheavy tank, and Titan hasn't met with materializing daemons, shredding up their insides, so something must prevent crafty Daemons from the feat. Since I'm not sure what it is, for now, I'll just say "Gellar Field".

Since the Imperium has no equal measure to thwart roving Choas possessing spirits, unless we deem that the Imperium can just teleport soldiers in, Loyalist Titans should have a Geller Field, which, while operational, makes it impossible for a Daemon to get inside, unless it is summoned from within.

No offense taken, I'm thankful for the honesty.

Well, as for the 'pilot' - It will have to be the tech-priest, and interfacing with the titan without the proper Princeps bionic interface will require a very hard(-30) willpower test, failure causes a level of fatigue for every degree of failure.

The fight itself will probably play out with the Lord of Change flying away(it has its own objective to complete and doesn't want to fight), the goal of the Titan crew/players is to stop it before it reaches its goal. The Greater Daemon of Tzeentch will probably be a difficult target to hit because of its size in comparison, and there will be daemons within the Titan trying to prevent the players from firing the quake cannon, and also attacking the 'princep'. So the players will have to protect the tech-priest, fight their way to a cannon, and then defend the player that is firing the cannon. Meanwhile, as the titan moves, large maintenance walkways that have degraded over time start falling into the gear housing, jamming the massive cogs and causing malfunctions until they are removed.

Interestingly enough, an Imperator Titan contains an Astropathic Choir to provide psychic defence and to act as a regional communication's hub.Also remember that greater daemons come in all sorts of power levels. A Titan on Daemon fight scene is awesome and I highly approve

In this case, I souldn't worry abotu weapon stats. I'd be runnign it as a set of skill challenges. Get teh Plasma Reacter online and firing at full capacity, overcharge the plasma conduits leading down to the primary weapo systesm. Oh no! Horrors are starting to marterialise on the top deck! Quick, Arch-Militant! Drive them off! Voidmaster lines up the shot. Navigator and Astropath are leading the choir in psychic defence, choir members are burning out second by second. The RT is screaming into the onboard vox, keeping everyone fighting against the chthonic and unspeakable horror before them. The Missionary is on the top of the great engine, spittle frothing his lips as he screams litanies of hate against the ninefold beast. The power level is building, but the Explorator calmly advises not yet, let it over charge, let it build a little further. Inside the advanced machinery of his mind he views an emotion, long buried, that he recognises as panic. He starts to chant his prayers to the Omnissiah, praying that the reactor will hold together long enough to overcharge the plasma annihilator, while watching his own growing panic with a detatched scientific curiosity. The beast approaches, the ground beneath it writing into a thousand different, mind shattering shapes. A rating kills himself rather than witness what happens next, and his body changes into something... else, something that the Rogue Trader must fight back from the Void Master as he calculates trajectories. The Void Master is suffering sensory overload like he's never experienced, the unfiltered combat feed from the titan's manifold dizzying even for a Moderati with centuries of experience. Here? It's burning him out and the Void Master knows that he needs to fire and detatch or have his mind devoured by the great engine.

The spawn is forcing the Trader back, step by step, as the Void Master gently presses the rune on the controls in front of him...

Interestingly enough, an Imperator Titan contains an Astropathic Choir to provide psychic defence and to act as a regional communication's hub.Also remember that greater daemons come in all sorts of power levels. A Titan on Daemon fight scene is awesome and I highly approve

I agree. However, you'd also need a chaos psyker shouting "Make my monster grow!". Aaaand a city obviously made of cardboard for the fight to occur in.

I agree. However, you'd also need a chaos psyker shouting "Make my monster grow!". Aaaand a city obviously made of cardboard for the fight to occur in.

and a guy baking lesser deamons in his stove.

Many of the weapons available to the Imperator are listed throughout products in the 40k line. Particularly ITA and Deathwatch: Rites of battle. The rules for the Warhound lister in RoB should give you a good starting point. The crew would include a Princeps (Which is VERY different from a tech priest!) and at least two Moderati who form the command crew. A tech priest (Probably NOT an explorator but rather a more traaditional "Engineseer" as presented in DH. Additionally; On an Imperator, There will be a number of servitors and support crew in addition to troops. It might be important to note that a Titan in general is not likely to deployed against any singular threat save maybe another Titan. Titan's are considered War engines used as a centerpoint to conquering major strategic objectives. 2 or 3 Ovelord class Battle Titans would probably be considered Overkill against a Hive! An Imperator would be the centerpoint of a Major planetary invasion on something like a Chaos held Forge world! The Space Marines in general and the Grey knights in particular would be the force most likely deployed against your Demon prince. Sounds like an Epic game though!

Thanks for the replies guys, I appreciate all the help. It was actually for a Dark Heresy game, and I think it turned out really well. If anyone's curious how it's applied, there's a thread in the Dark Heresy Gamemasters forums, but it has to do with a pre-made adventure, so there are many SPOILERS in the link:

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ACOLYTES FORBIDDEN
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