Obsidiux will stay out of the fight for the most part. He send out Flak ans Sirpent to attack. Note that, unlike the other battles, this one has a pattern; Flak and Sirpent alternate between each other, Flak constantly damaging all your warriors with Fire Storm, and Sirpent poisoning the current warrior. When both are killed, Obsidiux himself will come out onto the battlefield.
Quite a difficult boss to defeat because of his Elemental Shift and Mega Armour, sometimes warriors might have a hard time fighting him. But since his element is Air, use hard hitting Earth warriors to bring him down. However , his Elemental Shift ability can he a HUGE problem, as he can change element unexpectedly to cripple even strong ( but not too strong ) warriors.
Since Obsidiux was later to be defeated, King Boneshaker decided to kill off Obsidiux, but he was lucky enough to hide from his former comrades seeking out for him. His former allies still kind of trust him so he is still extremely is dangerous.
Dialogue ( Before this Boss Fight )
'I can seee you...smell you...taste your fear...I am OBSIDIUX, Harbringer of Darkness...I have come to reclaim our portal...your blood-soaked fate is SEALED!
Obsidiux was a former 2nd in command of Boneshaker's army.
Moonlight Meadow - Stage 8
Red River Rift - Stage 8