Most of the game is explained in the tutorial. It is a 2-player local multiplayer game.
TO USE SWORD SLASHER:
Sword Slasher is the most complicated character but can be pretty strong if you know how to use him. When you use his special, you are able to start inputting keystrokes. For player 1, use ", . /", and for player 2 use "1 2 3". These 3 inputs can be combined in different ways for different results.
The current keystrokes are:
111 or ,,,: Teleport forward
123 or ,./: Conjure a spear to launch forward
122 or ,..: Summon a sword to quickly fly around you
323 or /./: ORBITAL STRIKE!!!!
Good luck, and don't tryhard Sword Slasher too much...