No, there are no further boss battles that actually progresses the story mode. There are extra boss battles, name ly the bosses that you fight for the seven treasures (should still be available via wondermail wific).
It's the Darkrai battle, as also seen in Pokemon Mystery Dungeon Explorers of Time/Darkness.
You have to beat the game to battle darkrai.
in azurills nightmare. darkrai is the one causing the nightmare and is the boss of this dungeon.
Fight Darkrai
go though a dungeon with cresslia and when you reach the end you will fight darkrai
U find Darkrai in Dark Crater.
You need to get Darkrai on your team and suck his &½!^
dont no
No he's in explorers of Time,,darkness & sky
It dependes what level you are when you defeat Darkrai.
miracal sea 3F if ur holding a mystery psrt or secret slab
after egnima part, surrounded sea holding golden mask at 3rd floor,darkrai!