Daegon is the leader we all know that and he is in conflict with the Black Dragon, Kenshi, Takeda, Scorpion and Taven.
He is also helping Goro regenerate his arms and its possible that Kanos son is with him.
If Onaga is going to return do you think Goro could be his vessel created with maybe genetic samples from Reptile.
If you look at Goro and Onaga it could be possible i mean Shokans are half dragon right? and two of his arms could morph into wings.
And capturing Reptile brings the Red Dragon into conflict with Kotal and Outworld.
I would also like to see Devorah side with the Red Dragon for protection.