Puzzle games are oddballs. They're the only videogames that lack avatars.
An
avatar can be a virtual person (a Mii or Master Chief) or a set of
tools (such as a home in The Sims). In puzzle games, players don't
enter a gameworld, so they don't need avatars. The puzzles exist in the
real world. The falling blocks in Tetris and the colored gems in
Bejeweled are really falling blocks and colored gems (albeit pixelated
ones). Fiddling with them requires no digital intermediary.
This
makes the Nintendo DS the ideal puzzle game machine. With its
touch-sensitive screen, players are in direct contact with the
graphics. In Puchi Puchi Virus, those graphics take the form of
"viruses"-colored hexagons that gradually fill the screen. The player's
job is to touch three viruses of the same color, linking them into a
triangle. Once the viruses are triangulated, the player can pop the
triangle, causing the viruses to disappear.

