The Royal Knights Assemble - S1.E40

As Marcus and the others make their way to the Digital World, they end up crashing into a shoreline. To their surprise, they find Gotsumon there, reborn and without his old memories. Gotsumon agrees to lead them to Yggdrasil, but along the way, they are attacked by Craniummon. Just as ShineGreymon gains the upper hand, Gallantmon and the other Royal Knights show up and defeat him. Yggdrasil reveals himself, but Marcus, determined to not give up, throws a punch at him, only to find the shock of Yggdrasil's true identity: his own father, Spencer Damon.