This is Mu Can's plan, in which the most crucial part is that Mu Can needs to successfully pass the final trial and gain the ultimate inheritance of Tongshen Mountain. Only by doing so, can he ensure that his memory will not be sealed, and have the opportunity to search for others. The two little dragons he gave to MuMu and Ada act as such markers to help locate their positions, so Mu Can won't lose track of the two after he leaves.
However, most of the spiritual power within the two little dragons' bodies has been absorbed back by Mu Can, so the strength of the two little dragons is no longer as formidable as before.
As two streaks of blue light flashed by, MuMu and Ada had already disappeared from the spot, leaving no doubt that Mu Can and Xu Liang had won the second battle.
"Big Brother Mu, I have something to tell you," said Xu Liang, looking at Mu Can.
Mu Can thought to himself, "I thought you'd be able to hold it in and not speak."