Are you the rightful king or just a dirty peasant?
The one who pulls out the sword will be crowned king is a short game about pulling a sword from a stone to be crowned king, like in the Arthurian legend.
Grab the sword with your mouse and try to pull it out from the stone. If you are able to get it all the way out, you will prove that you are the rightful king and as such you will be crowned.
The Steam version of the game includes the online mode King of Kings in which the sword gets longer and heavier each time someone manages to pull it out.