Marvel and Attack on Titan are crossing over.
MARVEL AND ATTACK ON TITAN ARE CROSSING OVER.
Marvel and Attack on Titan? CROSSING OVER.
Japan. 2 weeks. Marvel. Attack on Titan. Crossover.
CROSSING OVER - MARVEL AND ATTACK ON TITAN.
So yeah, apparently Marvel and Attack on Titan are crossing over? Not much is known about the project at the moment, other than two very popular universes are somehow being meshed together (non-canonically). It's not entirely out of left-field though - the 3D Maneuvering Gear of AoT has always pretty much been "What if Spider-Man were a steampunk anime kid?"
Sadly, there aren't really any great Marvel/AoT themesong mashups, so we'll have to settle for this Marvel vs. Capcom 3 one: