My entire group is moving away this summer... How should I prepare for the break-up both in life and in-game. I need time to build a campaign and its ending before the end of summer so the sooner I have this sorted out the better.

Previous experiences are appreciated.

No previous experiences with a campaign like that, but I feel it should either be about "going out with a bang", or end with the player characters "retiring" into positions suitable to both their role and their personality/ideals (example: the cleric becoming a Bishop, the Guardsman becoming the captain of a company of Inquisitorial Storm Troopers assigned to protect an Inquisition fortress, the Assassin becoming a mentor training the next generation of Inquisition operatives) as well as their in-character age (if they're younger, perhaps the cleric would instead become a Missionary heading out into the unknown to spread the Emperor's Light by accompanying a Missionarius Galaxia mission, the Guardsman just becoming a lieutenant, and the Assassin transferring into an Assassinorum Temple or becoming a Rogue Trader's secret bodyguard).

If the players are so inclined, their characters might even be mindscrubbed and released into a cozy civilian life with comfortable positions in the court of some noble their Inquisitor knows. Or you could mix the bang and the retirement, with some characters sacrificing themselves and only the survivors being retired.

Whether you are aiming for closure by epic sacrifice, or by actual retirement, should depend partially on what happens in the campaign, but of course also partially on the players' assumed preferences, as it's sort of a farewell gift from you. Either way, make it grand , Mass Effect 3-style, with various contacts, enemies and favourite locations from your previous games showing up for one final performance whose outcome would affect at least an entire planet, if not an entire sector or the very fate of the Imperium, with the player characters at the forefront of whatever resistance the Imperium musters against the threat you conjure. The kind of stuff you'd read in a novel or watch a movie about!

As to the nature of the threat, again I'd probably recommend looking to the players and guessing what sort of enemies they enjoyed to be pitted against the most, but also consider the possibility of enemy alliances, both to build up the threat (by providing the enemy with greater resources to accomplish their dark deeds) but also to throw several different types of hostiles at your players, and challenge them in different ways. Perhaps what begins as a conspiracy between noble Houses is revealed to include alien intervention (Dark Eldar mercenaries hired as assassins? Tyranid organisms foolishly used as a biological weapon? secret collaboration with the Tau in preparation for secession?), and culminates in a daemonic manifestation as some sort of twist reveals one of the influential nobles (unsanctioned psyker?) to have played both the Xenos as well as the Imperials against one another.

Just off the top of my head - I'm sure people can come up with more clever plots when more time is invested in brainstorming.

Or end with a cliff hanger, so you got an excuse to get together again a couple of years down the line! :-)

Whoah, slow down there, Horus.

You can go one of two ways, end your campaign with big old fight where you win or die.

Or, have them finish a mission and then have the players part ways. Each going back to their normal lives. No further contact with the inquisition required. Some things just aren't their fight.

These guys like an epic battle...

I think I'm going to have a tech-heresy themed campaign.

*cough* will need titan stats *cough*

Don't stat things you don't want players killing.

Much like Pathfinder's folly was stating cthulhu.

Oh, I'm fine with them killing it...

Any titan of the reaver class or bigger is simply invulnerable against mere individuals.

The Void Shields of Warlords or Emperors are capable of tanking lance strikes not to speak about the armor behind those shields.

Unless they bring several armored formations and some super heavies there is no way to defeat such a titan unless they actually board it in a semi narrative/combat fashion - and that is quite a feat.

There are just two "relaible" tactcs for infantry. Swarm it, bring heavy equipment, cut its outer doors open resulting going straight against the interior defence of such a titan and having to cross distance in the first place or doing it the Titanhammer way.

Just be ballsy like friggin Lysander and try to teleport yourself with terminator armor behind the void shield right onto the bridge of this beast and unleash what ever firepower you have.

If you want to stat it against all that regular humans can bring - besides an entire army - roll a d100. On a 1-100 the titan takes no damage. If the titan shoots its blast is bigger than anyone can dodge and it will instantly kill anything smaller than a friggin huge warmachine.

Any titan of the reaver class or bigger is simply invulnerable against mere individuals.

The Void Shields of Warlords or Emperors are capable of tanking lance strikes not to speak about the armor behind those shields.

Unless they bring several armored formations and some super heavies there is no way to defeat such a titan unless they actually board it in a semi narrative/combat fashion - and that is quite a feat.

There are just two "relaible" tactcs for infantry. Swarm it, bring heavy equipment, cut its outer doors open resulting going straight against the interior defence of such a titan and having to cross distance in the first place or doing it the Titanhammer way.

Just be ballsy like friggin Lysander and try to teleport yourself with terminator armor behind the void shield right onto the bridge of this beast and unleash what ever firepower you have.

If you want to stat it against all that regular humans can bring - besides an entire army - roll a d100. On a 1-100 the titan takes no damage. If the titan shoots its blast is bigger than anyone can dodge and it will instantly kill anything smaller than a friggin huge warmachine.

I'd suppose the techies building the titans considered these tactics too. Which is why there are infantry companies stationed in the legs. And aren't void shields teleport barriers?

Still, an aerial assault (perhaps using jumppacks or valkyries) to get to an unguarded hatch somewhere on the main body (dodging AA fire) and then inside a titan to sabotage it would be kinda epic.

I'd suppose the techies building the titans considered these tactics too. Which is why there are infantry companies stationed in the legs. And aren't void shields teleport barriers?

Still, an aerial assault (perhaps using jumppacks or valkyries) to get to an unguarded hatch somewhere on the main body (dodging AA fire) and then inside a titan to sabotage it would be kinda epic.

Titan Void Shields can be teleported through though teleportation on its own - without a beacon to aim at - is always extremely dangerous and top notch technology. Also you need gear that allows teleportation in the first place.

Aside from Tech-Guard roaming the titans interior you might also expect some sort of murder-servitor or interior turrets to protect the Titan. Basically there is nothing that would not be employed to defend a titan for a loss to mere infantry boarding would have occurred more often.

The only occasions I remember at the moment where such a things successfully happened were orcs boarding Titans at Armageddon where they had a massive amount of boys, kommandos and whatever and could sustain the losses of the sheer problem to board a titan in the first place or the Titanhammer Tactic, sciping all the interior defense by bypassing it via teleport and bringing the death blow right onto the bridge. Lysander pulled it off so perfectly because he is afriggin killer-machine and the Fists are just extremely good Terminators. Other Chapters might use this tactic too though without a special character this might actually be a suicide mission. Taking down a Titan with 5 Terminators though is a pretty good deal.

An aerial Assault might bring you on a titan unless you bring some extreme amount of firepower and wargear with you that wont help you much. You still have to fight your way through an unknown territory that is a maze where the enemy might know your very location all the time, sending murder servitors, cutting your corridor off and filling the air with VX Nerve Gas shooting with stationary heavy-bolter turrets at you and what not.

There is a reason why it takes countless orks or the angles of death to do that job. I would consider that the big bang of some Deathwatch game though for Dark Heresy it seems quite warlike for me and I would suggest some investigative showdown maybe resulting in the classic encounter against a radical inquisitor and his own personal entourage if you are hereticus, some planetary governor that pledged his soul to chaos, sacrificed a shitton of people being on the brink of a full daemon incursion if malleus or some dark eldar pirate that had pillages some area for quite a time with some double agents among the human population when they are from the ordo xenos.

In my interpretation an inquisitorial cell has only fighting capabilities for the rare occasion when it is actually needed and cant be avoided. Though that is not the job for such a cell unless the inquisitor is quite secluded.

Most other inquisitors that do not rely on one entourage and have a power base simply requisition guardsman to do that or rely on their personal kill-teams of inquisitorial stormtroopers - simply having the right tool for every occasion rather than to rely on some multitool that is decent at everything but not good at anything.

There is a reason why it takes countless orks or the angles of death to do that job.

Or a single Ork on a bike crashing through a Titan's cockpit.

Wazdakka Gutsmek - the bane of the Collegia Titanicus.

I also recall a super-old snippet about a single Sister of Battle doing a guerilla war in the insides of an Ork Gargant, spending days with moving through its internals and doing hit & run strikes on critical systems and repair crews until that thing finally stopped moving. It's been ages since I last read it, so take that with a grain of salt.

Wazdakka Gutsmek - the bane of the Collegia Titanicus.

Sometimes you just have to appreciate the fun that Orks get up to.