As you explore the depths of Another Crab's Treasure, you'll occasionally come across large purple rocks with Umami symbols on them that you can't destroy no matter what you do.
How to Destroy Purple Umami Blocks in Another Crab's Treasure
Considering that they have the Umami symbol, you'd think that using a shell's Umami ability would break them, but that's not the case. You'll have to find a skill to crack them open much later, so be prepared to do a lot of traveling and backtracking to figure out what was inside.
To break open purple Umami Blocks in Another Crab's Treasure, you'll first need to battle the Expired Grove area's secret boss, Topoda, to obtain his adaptive ability, Mantis Punch.
You reach Topoda after defeating the main boss of the area, Heikea, and grabbing the map piece you need for the main story. Before you head back, go to the locked door in the boss room and to the right there is a drop that takes you to Curdled Village.
