Character idea: Shadow Yoda

A character which could be considered for Galaxy of Heroes is Shadow Yoda or Darl Side Yoda.

Whilst on the Wellspring of Life planet aka the Force Planet, Master Yoda would encounter a personification of the dark side that existed inside him. This dark side manifestation was a Gollum-like figure which crawled on its hands and legs and fought using its hands. By rejecting its existence, the figure was resilient to Yoda's attacks, however when Yoda acknowledged its existence he was able to control it and thus defeated it.

Shadow Yoda upon its defeat.

Unlike Rey (Dark Side Vision) which represented what Rey could be, Shadow Yoda was the manifestation of the dark side that surprisingly existed in Yoda.

The full fight between Yoda and Shadow Yoda can be seen here: https://www.youtube.com/watch?v=ctoWE_2iJOw