Henry Hatsworth and the Puzzling Adventure is split into two modes of gameplay, platformer and puzzler. The platforming action takes place on the top screen while the puzzling action is restricted to the bottom (utilizing the touch screen controls). However, everything that happens in the top is affected by the bottom and vice versa.
The platforming part is pretty straight forward. Henry jumps, slashes enemies with his sword (or shoots them with any variety of weapons) and gathers power ups, and like any good platformer, there are there are air worlds, water worlds and more. However, for any enemy to really be defeated or any power up to take effect, one must destroy or activate them in the Puzzle Realm as well.
The puzzler portion plays like Tetris Attack in which blocks must be lined up in rows of three matching colors. The rows are constantly moving upward. Enemies that are defeated in the real world turn into blocks in the puzzle realm and if they are not defeated there they will come into the real world and attack! However, in order to get into the puzzle realm you must build up your puzzle meter by attacking enemies and advancing through each level. It sounds complex, and it is, but once you get the hang of it it becomes second nature, old chap!