From Bulbapedia, the community-driven Pokémon encyclopedia.
Flower Power (Japanese: あつめてバタフリー Gather Them, Butterfree) is the name of an e-Reader application from the Expedition Base Set. It is a minigame featuring Butterfree. Three cards are required to play Flower Power: Caterpie, Metapod and Butterfree.
In Flower Power, the player takes on the role of a Butterfree. The objective of the game is to touch as many flowers as possible while flying on a side-scrolling screen. The game is over if Butterfree touches a Beedrill, Koffing, or Rattata blocking its path. The e-Reader will save a player's high score, even after the game has been turned off.