Part 1 There are 2 pink glowing crystals. One is at the samurai maze(past the abyssal void), it gives you a free move by just clicking on the round purple crystal. The move is called “Precise Crystal Spike Attack” you literally just punch into the ground and some crystal spikes appear the move itself is an ok move, small damage.

Miyajima progression Part 1 locations.

Part 2 The other pink crystal is in Miyajima cave(in-between stone and sand), where crystal ore spawns. Upon talking to the pink crystal you get a “Schematic Crystal Prison” and to get the actual move you need to mine 50 crystals from Miyajima cave and obtain 1 chakra fragment from killing ramen boss and then crafting the move at an anvil.

If you go straight forward to the left of the Abyssal rift you will find the Miyajima cave eventually (Near Stone Village)

Miyajima Cave