Oh, chaincomplex, is that horrible unknown effect a [fear] effect?

If yes, then Ux Utanar can expend one use of Knight's Challenge to allow a reroll with a +11 modifier for Myriad. In which case I'll re-write my turn completely, since I can't teleport away anymore. Myriad would still be under the effect of the attack, but only for the duration between the obyrith's attack and Ux Utanar's turn.