13 Most Difficult Boss Fights From The 1990s

MewTwo – Pokemon Red/Blue/Yellow

If you saved the Master Ball for this very encounter, then MewTwo is a walk in the park. For those who didn’t or couldn’t, it would unleash all manner of psychic hell on your team. Even if you deal damage, MewTwo can use Recover to regain its health and then raise its defense with Barrier. Defeating it is possible with high level Pokemon but if you’re aiming to capture it without a Master Ball, it can be a pain.