About the game:
Nidhogg is a side-scrolling two-player fighting game by Mark "Messhof" Essen. Players duel with swords in a pixelated environment. Players can run, jump, slide, throw their swords, and fistfight.

The player-character's sword can be held at three different heights: low, medium, and high, and changing the sword's position to hit the opponent's sword will disarm the opponent. Players can also dive kick, wall jump, climb ledges, and crawl.

The player continually pushes towards one side of the screen, such that they are permitted a few seconds to run towards their opponent's side while their opponent respawns after dying. The player to reach the end of their opponent's side first wins and is eaten by the mythological Norse serpent Níðhöggr.

Trailer:

Gameplay:


Official site: http://www.nidhogggame.com/

It's a pretty fun simple game, you can buy it through steam too! Enjoy.