  We establish some general schemes relating the computational complexity of a
video game to the presence of certain common elements or mechanics, such as
destroyable paths, collectible items, doors opened by keys or activated by
buttons or pressure plates, etc. Then we apply such "metatheorems" to several
video games published between 1980 and 1998, including Pac-Man, Tron, Lode
Runner, Boulder Dash, Deflektor, Mindbender, Pipe Mania, Skweek, Prince of
Persia, Lemmings, Doom, Puzzle Bobble~3, and Starcraft. We obtain both new
results, and improvements or alternative proofs of previously known results.
