Most likely the Winter Soldier. Maybe Alex will save Bucky ahead of time and take him with him and destroy Hydra along the way. It is also worth showing that Notch is not to be trifled with, otherwise someone will suffer greatly
Imagine the reaction of the X People when people start talking about Notch's car, with the exact same color and body kit as Alex's? Well, there can be no such coincidence! They'll probably think that Notch and Alex are at least familiar with each other
I really hope Alex releases a game developer package so that we can see other companies use the full immersion. Not just games like Halo or Fallout, but Microsoft Flight Simulator. Just have the companies pay a low royalty fee and Alex will be swimming in money.