Insomnia

Insomnia prevents the Pokemon from falling asleep under any circumstances. Sleep-inducing moves like Spore, Sleep Powder, Hypnosis, and Yawn all fail against a Pokemon with this ability. Crucially, this also causes the move Rest to fail entirely — the Pokemon cannot voluntarily put itself to sleep either, which removes a common recovery option.

If a Pokemon acquires Insomnia while already asleep — through Skill Swap, for example — it wakes up immediately. The same applies when a Pokemon regains Insomnia upon leaving battle after it was suppressed. Functionally, Insomnia is identical to Vital Spirit — both provide complete sleep immunity with the same mechanics and interactions. The only difference is thematic: Insomnia suggests the Pokemon cannot sleep at all, while Vital Spirit implies the Pokemon is too energetic to doze off. Found on 17 Pokemon including Murkrow, Honchkrow, Shuppet, and Banette, Insomnia has been available since Generation III.