Hammer of Avernii

Each time a model from your army with the Oath of Moment ability makes an attack that targets your Oath of Moment target, you can re‑roll a Wound roll of 1.

Once per battle round, after your Oath of Moment target is destroyed, if a Caanok Var model from your army is on the battlefield, select one enemy unit visible to that model. That enemy unit becomes your Oath of Moment target until you select a new one