OOC: Quick mid-turn update while Hyal and Ved get in their posts.
Indominus fails but he's going to use a legendary resistance. He's also going to use a legendary action on Niko's turn to activate wild rage.
Niko. You sheath your blade is umbral ice and Indominus knows what you're going to do next. He hasn't lived this long by accepting sucker punches. Before you even begin speaking, his eyes flash red and an aura of tumultuous silver energy begins flashing around him. Then some kind of holy light wraps around both him and the dragonborn. The Dragonborn man never moves, remaining seated and appearing calm even once bound. Indominus turns his gaze towards Barkvin and vanishes.
Barkvin, Murdain and, I believe, Hyal. You see Niko draw her sword and Barkvin casts his spell. Then Indominus just shrugs that spell off and vanishes in a flash of- "Well well well, my pup brought her pack with her," you hear from just behind you.