The Mutant Massacre was the arc that welcomed me into the loving arms of the X-Men. I wasn’t sure how I’d game it until someone posted this pic on tumblr. As I recall, this was in the back of every issue of the Mutant Massacre so we could follow along to the event that saw angel crucified, Thor’s arm broken, Colussus paralyzed and Nightcrawler put into a coma – not to mention Wolverine vs. Sabretooth Parts 1 and 2 and Storm getting her powers back.
Start a game by dropping this picture onto the table. Each issue is a session or less of play and players can swap out characters between issues. It might be helpful to name each issue before we start playing but just in case, here’s the name of each issue:
X-Men #210: The Morning After
X-Men #211: Massacre
X-Men #212: The Last Run
X-Men #213: Psylocke
The New Mutants #46: Bloody Sunday
Thor #373: The Gift of Death
Thor #374: Fires of the Night!
X-Factor #9: Spots!
X-Factor #10: Falling Angel!
X-Factor #11: Redemption!
Power Pack #27: Whose Power –?
Also useful: Marvel Milestones.
Fun.
Githyanki Diaspora 
One of the things about this Event, if you were do it, is to think about what the consequences of the Massacre really are.
In the comics, the main repercussions are that Angel loses his powers (and commits suicide, only to come back as Death).
Several popular X-Men are overcome with seriously bad trauma, and we end up with the X-Men on the move, recruiting (in hindsight horrible) new members.
Wolverine learns that Jean Grey is alive again, though he keeps this information from his teammates; he also encounters Sabertooth for the first time in a long while (first published encounter). Retroactively, we learn that Maddy Pryor was a target and someone stole Cyclops’s baby.
All of which is… well…. weak sauce when you consider how incredibly impressive this seemed when it debuted. It starts out as this “Holy shit, what are they gonna DO?!?!?!?!” thing, and there’s never really much closure. It just kind of peters out.
Part of the problem is that the Marauders, and Mister Sinister, are terrible villains in that they really have no motivation. (As I understand it, a motive was supplied about 10 years later, but come on.)
It might be more tempting to remove the Marauders and replace them with the Right (as proto-Sentinels), Nimrod (who had been a pretty formidable adversary in X-Men 208/209), or Freedom Force (who have to earn their badges by bringing in mutant scalps, though it’s hard to imagine Mystique allowing that). A really radical approach would be to replace the Marauders with X-Factor, the mutant bounty hunters, and have the massacre occur as a tragic accident.
Interesting!
All of those sound like fun.
I think arcs that we find unsatisfying make for the best gaming. The re-writing is even better.
One thing to think about in the X-Universe around this time is WTF was going on with Scott, Jean, and Storm, which pretty much drive all of the events from X-Men 200 (1985) through X-Men 240-ish (1988).
To shorten a terribly long post, Scott abandons his wife and child WITHOUT ANY EXPLANATION and then NEVER CHECKS UP ON THEM. (Granted, his own father preferred to have sex with a space-skunk rather than visit the orphanage even once, so it’s not like he had good parenting role models.)
This is unquestionably the most interesting thing Cyclops has ever done until, say, Morrison pairs him up with Emma Frost. It is a Pym-level breakdown, and everyone treats it as perfectly normal behavior.
The Scott vs. Maddy super-separation bubbles along for like 40 issues until Inferno, which is like a super-divorce. And it turns out that, gosh golly gee, Cyclops isn’t a deadbeat dad thinking with his dick–no, he heroically saves the world from a vengeance-obsessed, child-killin’, demonic psycho clone. In the face of such evidence, New York Family Court has no choice but to award custody to the absentee father.
(And this ties into the Massacre because, like, Sinister was behind everything, or something. Who the hell knows.)
But really the kick-off here is that Jean Grey is back. What happens to Scott, Maddy, Logan, and Ororo (who was supposedly Jean’s best friend)? With a 4-person cast, maybe roping in Alex and Lorna too, and God help us Cable, it would be a kind of interesting mini-scenario–like “In Utero” for Sorcerer….