The Demons And The Crabs

Kill 20 Hermit Crabs by chasing the off the edge of the map.

How To Unlock
The challenge calls for you to kill a total of 20 Hermit Crabs by chasing them off the edge of the map.

The first major hurdle is that the crabs first spawn in the fourth level, and there are no ledges there. So the run must be looped, as the crabs start to appear in every level of the looped run. The Roost and Titanic Plains have very visible edges, so just find a crab(look for their mortar shots), approach them and they should start running. If they at first don't pop up, hit them once.

While chasing 20 crabs off a ledge while there are potentially high-level enemies chasing you might sound difficult, don't despair.
 * This Challenge can be completed over multiple runs
 * Be careful not to pick up drones or items that passively damage enemies, as they might kill the crabs before they get to the ledge.
 * Some Prismatic Trials may give modifiers that make it easier.