Rogue rapids

https://en.wikipedia.org/wiki/The_Rock_Jockeys

Rogue rapids are theoretical surviving rapids who escaped from the Wumpa Archipelago following the end of the Mutant Vortex Crisis. There have been many campaigns conducted to find any dissident rapids, who have been collectively termed "units of the devil". The most significant campaign is the Wumpa Initative Munition Campaigns.