As the trailer suggests, this game is a humorous cross between puzzle platformer and lemmings, where you take advantage of the deaths of your predecessors to progress through the different levels.
With an unlimited number of knights at your disposal, you control one until it dies, then another, and so on, and on each try to die in a way that your corpse will be of some benefit to your next knight. But doing well at a level means using fewer knights (wouldn't want them to die in vain, right? ;)
Progressing in the game uses more of your puzzle skills than your platforming skills, and for considering you will only be using 3-4 buttons, the game gets surprisingly complex.
Completing the various levels and achievements feels reasonably satisfying, and it can be amusing to overcome any obstacle by throwing numerous knights at it in various ways.
The game contains several references to other games, most of which I found quite amusing, but more than anything else I found myself laughing out loud at many of the messages describing how varyingly successful I had been at the end of each level.