Board Thread:Theories and Rumors/@comment-24318569-20150712090731/@comment-26509603-20150715215615

Punchappy4 wrote: It's not really been confirmed rather Shadow of Ronin is canon or non-canon.

Actually, I believe it has been confirmed (by one of the people working with the show). The confirmation is justified when the Ninja recognized Ronin, and when Kai confronts him by saying, "You left us in the mouth of a-" (he didn't get to finish his accusation) indicating in Shadow of Ronin when he left the Ninja in the mouth of both a volcano and an interdimensional portal.