I've always quite liked the Butterfree evolution line. I recently considered them in terms of game design.

The Butterfree line either introduce or reinforce nearly every major game mechanic, and do so early.
By raising a Caterpie and their Starter, the player is introduced to attacks, special attacks, status, buffs and debuffs, type advantages and weaknesses, evolution, and abilities. All before level 20, around the second gym in Kanto.

#pokemon #caterpie #metapod #butterfree #Tropeifier