Pokémon: 10 Craziest Evolution Methods The Games Made You Do

Runerigus is a Pokémon that is half badass Stonehenge, half riddle, as it's literally impossible for anyone to evolve it without knowing exactly what it needs to get there.

For starters, you need your Yamask to take at least 49 points of damage - and any health taken by weather effects or statuses like poison don't count, so good luck with the possible maths you'll have to do, you brave, brave fool. After this trial in hurting your own Pokémon, you need to take your poor, beat-up buddy to the rocky bridge-like overhand in the Dusty Bowl, and then run under it, finally completing the weirdest task in the game.

Weirder yet, it's never fully explained why this does what it does, so you're left with a strange haunted snake rock, and a whole lot of unanswered questions, mostly around the fact you may or may not have just summoned a demon to come with you on you fun family-friendly adventure.