After you find a sword, you become cursed and now only have 1 minute until you die...although you just respawn with any collected item. This means that you have one minute to complete an objective, but first you need to work out what you need to do. At many points of the game, you have a few options where to go. You may come to a location where it seems you cannot progress, so when you respawn, you should venture down a different path.
You don't have to wait until death, you can force it to happen at any time with the B button.
It's part exploration, puzzles and memorisation, and played at a rapid pace. It's almost like the 2D Zelda's but mixed in with the Wario Ware madness. The monochrome style makes it feel very retro, like it could be on the GameBoy.
You find new buildings which act as checkpoints, and you can return to previous houses to set the checkpoint there instead. If you know you need to backtrack, you will first return to the house.
It's quite a cool idea, but will only take 1 to 1.5 hours to get through. You could return to the game for the New Game Plus, or try and improve your times/death count. There are also coins to find, which I presume allows you to venture into the underground temple.
It's quite a cool idea but it's over far too quick.