Toribash.
Toribash is a Single Player and Multi player game.
This is a gif of a guy humping a wall... and his own head.
This one is of the Wind Mill mod.
The main objective of the game is to do the most damage to the other player. Or to mess around.
It has mods you can use such as swords and hand-saws.
Do the tutorial before anything else. You will need to. Its a complex game once you start playing it for the first time.
I suggest you play single player before multi player. The people on multi player will make you wish you never played the game. Ever.
To move your player, you pick either to Hold, Relax, Contract, or exstend joints. You can also grab the other player or yourself.
There are many maps. Just try it out. I played it once and now I'm addicted. :D