The Red Horns decided to engage the northern most undead pressing in on their guide. Letting fly the Yklwa at the creature.
At the same time he uttered a word in that terrible speech that the writings on his skin had forcefully taught him. At once the twig creature arose and moved next to their guide, attacking the zombiefied girallon.

Spoiler
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Get within 10ft of skeleton
Ranged attack with Yklwa against northen most skeleton

(1d20+8)[15], damage (1d8+6)[7], if crit (1d8)[4]

Afterwards gain height again

Bonus action:
Command Steel Defender to protect Quawasha, with Deflect Attack (disadvantage for Girallon)
attacking the same skeleton as TRH
Force-Empowered Rend. (1d20+7)[11], damage (1d8+2)[4], if crit (1d8)[4]