The Osman Family's aid wasn't part of the regular forces Medivh had taken into account.
With another trump card in hand, that was a good thing. If the third phase of the Light Covenant ran into trouble, the Osman Family's support would make it easier for the Wrynn Alliance to weather the crisis.
"Those ignorant fools have no fear. These Mushroom People and Bone Frames actually think we can't deal with them!"
When they discovered that the Sam Plane was a Spore Plane, the Abyssal Demon Lords who had once suffered at the hands of the Myconid and Bone Spirit grew sinister expressions.
They had never forgotten that grudge. They had planned to wait until the Abyssal restrictions were mostly lifted, then smash those creatures' shells and teach them a lesson.
They hadn't expected the Myconid and Bone Spirit to be so arrogant. They thought they'd be unmatched after leaping to a Ninth Rank plane, and had now leapt to a Tenth Rank plane, acting as if no one could touch them.
The Star Sea outside the Sam Plane was already filled with the Abyssal Demon army.
The Abyssal Demon Lords who couldn't squeeze in were massing their forces outside other Spore Planes.
As soon as the landing battle on the Sam Plane began, they would attack the other planes in the Spore Jungle at the same time.
They refused to believe that, under these circumstances, the Myconid and Bone Spirit could defend every front and stop them from reaping their harvest.
"You Mikuang, take your forces and help the defenders of each plane clear out the invading Abyssal Demons."
While the Abyssal Demons stirred restlessly, Medivh was busy mobilizing his reserves.
He ordered You Mikuang, the first Holy Remains Monarch to be born, to lead the Holy Light Skeleton