Here's the image of the announcement from it's Facebook page:
I personnaly didn't know this game. According to the description on the official website,
Here is a gameplay video where we can see his abilities, and how he looks and move in game:Soul Hunters is an innovative Hero Collection RPG game that combines the fun of a real-time
strategy (RTS) with unique multiplayer dungeon raiding challenges!
Others Ubisoft's characters were also added in Soul Hunters before, Ezio Auditore from Assassin's Creed and the Prince of Persia.
It's a little bit surprising to see Rayman appears in a game of this kind, what do you think?