しみ, そ, し
A tsunami runs into nine trees and produces a dye the color of the forest. The tsunami water mixes with each tree, nine of them actually, and the resulting liquid is a forest green dye.
The dye continues to pass through the forest and hits a group of centaurs (せん). Now each centaur is dyed with the forest green dye. They don’t look happy.
Currently there are no similar looking kanji which exist in the WaniKani learning system