Alex Mercer (prototype)
Superman
Wolverine
Jack Harkness (dr. who/torchwood)
Harbinger (and by extension, all of the collectors)
That's only 5, but all of them are practically invincible. The other 2 consist of fictional characters from a universe that's mastered faster than light space travel, so they can teach me how to do it, so I can make some money telling various engineers around the world.
Superman
Wolverine
Jack Harkness (dr. who/torchwood)
Harbinger (and by extension, all of the collectors)
That's only 5, but all of them are practically invincible. The other 2 consist of fictional characters from a universe that's mastered faster than light space travel, so they can teach me how to do it, so I can make some money telling various engineers around the world.