While inside its cocoon, this Pokémon develops a pair of thin, bladed arms that remain fixed in front of it while it develops. If the cocoon is threatened, the arms can extend just enough to jab any predatory Pokémon that try to feed on it, delivering a poisonous sting. Most of the time, however, predators are scared off by Kakuna's menacing eyes.
Kakuna always give off a high level of heat, making them very warm to the touch. They usually nest in trees, hanging from branches by silky strands or even stuck to rocky surfaces in the mouths of caves.
Being a Cocoon Pokémon, Kakuna has a very limited moveset.
- Poison Sting - Kakuna usually retain this ability from their Weedle phase, stinging predators with their short arms if they get too close.
- Shed Skin - Kakuna can shed epidermal layers should it be afflicted with poison, casting off the infected tissue before the poison spreads.
- Harden - Kakuna can grow additional epidermal layers to reinforce its shell.
Kakuna evolves into Beedrill and typically hatches from its cocoon at Level 10.