Normally this would be a confidential report to the Trenchcoats and the X-Men, but since you were all impacted by this, I wanted you to know what happened and what was done to prevent it happening again. If you're mature enough to fight, you're mature enough to be told the truth.
The mansion was invaded by demon's under the control of a character called Belasco. The old-timers might have recognised them - they were the same sort that attacked the mansion last time, back in 2004. Belasco wasn't in control of Limbo any more, but he'd set up his own little mini-dimension with the remnants of his demon army and he's been building up since. To attack us, since he sort of has an old grudge and because mutants are good weapons once you corrupt them enough. So he nabbed a bunch of people with the plan to keep them under lock and key until they were corrupted by the dimension enough for him to use - probably to retake Limbo, but it's not like he told me all his plans. Villains - real villains - never do.
I won't go into details about the bit in the middle, since that's personal to those who were there. Better to cut to the end - a group of X-Men that Scott, Jean and I picked out, based on them never having been possessed or gone evil or had certain personal weaknesses and such, went through a portal Strange and Topaz opened. Billy went too, to keep the portal open from the other side. There was fighting, our people were rescued and Belasco is very definitely dead. The dimension itself is gone too - there was kind of a magical boobytrap activated that undid all the magic that held it together. So, no more demon lord, no more demons (from him, any way) and apart from a couple of people, everyone's home and safe and should be back to their old selves in a day or so.
I will apologise, though, for not being here when things happened. Doc Strange and I will be working on the wards, once my magic's back up to full strength, to avoid something like this again. But from what I'm hearing, people did good defending themselves and their friends. Well done.
Finally, I need some energy donors for a healing spell. Healing factors, super strength, super resilience, that sort of thing. No energy projectors or speedsters, since I'll burn you out too fast. And usually I'd say "no minors", but fuck it, after what you went through, you're all able to make informed decisions. Talk to me and Doc Jean beforehand and we'll decide from there.