Onyx Wendy (also known as Black Wendy) is a mini-boss in Primeval Island. It has the same build as Wendy of Trial Tower, but has a gorilla-like face, has darker fur, and is darker.. It is found in the room after the platform map (about the third room).
It has multiple attacks. Firstly, it has a roll and a breath like the regular Wendy. The Jump Attack it performs is differently, however, as it jumps the ground. Also, sometimes when it rolls, it may fall flat on the ground causing a shockwave-like effect that lifts up nearby opponents.
- There are Weapons designed after the Onyx Wendy.
- The card for Onyx Wendy states, "I will avenge my beloved Wendy", suggesting that it and Wendy are either related, or a couple. The statement may refer to the "ugliness" KoG gave to them.