This is a play-through using Thanos in the Arcade version of Marvel Super Heroes. Read on below for more information...
Thanos is the final boss in the game. He is an unplayable character in this version of it.
===== About Thanos =====
Powerful Marvel villain with a goal to impress a female entity. He does this by obtaining the Infinity Gems, taking control of the universe and wiping out half the lifeforms in the universe.
As a "large" character he is a bit slow and clunky in movement, but his moves make him an very overpowered character. Some of his basic moves are like special moves, for example his crouching [HP] where he rips up the stones; and the crouching [HK] where he stomps the waves at you. Both of these are powerful and have great priority.
Despite having the Infinity Gauntlet and it's Gem Supers, he can still use the "regular" Gems to power up.
===== Additional Information =====
--- Despite being an unplayable character, if you complete the game with him he has an ending with his own unique images, however the story text/dialogue are of Magneto's.
---- When playing as him in single-player mode, if you lose a match, he appears on the Continue screen perfectly. Sometimes you'll get the advice text in Japanese, even in non-Japanese versions of the game.
===== About Marvel Super Heroes =====
The next game after X-Men:COTA, Marvel Super Heroes had a lot of living up to do. The gameplay is more refined and solid than COTA, and is generally a better-built game overall. The graphics, animation and action however, are far less intense and less frantic than COTA.