Indomitable CPU

The Indomitable CPU is a treasure in Pikmin 2; it is actually a  (vacuum tube), with the text:  preceding person system .

The treasure is dropped by one of the Gatling Groinks on sublevel 7 of the Subterranean Complex in the Valley of Repose upon its defeat. There are two of these enemies on that level, but the one that carries it is always the one atop a tower. Attack that one from behind, preferably with Purple Pikmin. It is recommended to clear the area of bomb-rocks before venturing out with Pikmin, as they can be easily set off in the fight.

Note that because of the way sublevel generation works, it is possible for the Gatling Groink to not spawn, and as such, for the player to be unable to obtain this treasure unless they reset and try a new sublevel layout, as detailed here and here.