No need for manifestation, that F9 Nighmare already made me hide behind the sofa
While in the astral all their attributes are equal to force, so it's rather easy: The Nightmare 9 uses one attack:
Astral Combat:
18d6t5 3DV 12
Manabarrier resists:
Resist:
16d6t5 6 [16d6t5=5, 2, 5, 6, 6, 2, 2, 4, 2, 2, 3, 4, 5, 1, 4, 5]
Barrier takes 6 damage, 2 points remaining
Nightmare 8
Astral Combat:
16d6t5 5 [16d6t5=6, 3, 1, 2, 3, 2, 3, 5, 2, 6, 6, 6, 3, 3, 1, 2]
DV 13
Resist:
16d6t5 2Barrier takes 11 damage, shatters.
The other 11 manifest
Followed by Isaint giving the team the command to run away and not look back.