This is a tool-assisted speedrun. For more information, see http://tasvideos.org/3453M.html. TAS originally published on 2017-07-03.
Contra: The Alien Wars is the third entry in the Contra series. Like its predecessors, it is a predominantly side-scrolling shooter with a heavy emphasis on action. The protagonist can fire in eight directions when standing still. New abilities include climbing on walls, grabbing poles and navigating tanks. Parts of scenery can be destroyed. Originally released on the SNES, this version of the game was released on the Game Boy in 1994.
ThunderAxe31 (http://tasvideos.org/ThunderAxe31.html) makes quick work of this game, jumping and shooting his way through aliens as fast as possible.