The disguised spirit pauses just long enough to see what Heather will do, and growls under her breath "You're not getting my charges today...." as she casts a Heal spell on Casmar, and sees about getting above the metal monstrosity as best she can.
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Delay until Heather goes. After that:
Standard: Heal. Caster level 14, so 140 HP restored.
Move: Fly up diagonally to try and get above the beast. If I get a Haste from Heather, great! I can. If not... oh well, at least I'm right next to it.