2. Make relevant choices — Riftbound Rules

Section 402 — 5 rules

402.1.: Make all choices required for this ability, such as targets, modes, or other relevant decisions. See rule 349. Playing Cards for more information
402.2.: If legal options are not available for an Activated Ability, it is not legal to activate it.
402.3.: If there are not enough options to make legal choices for a Triggered Ability that has been put on the chain, remove it from the Chain now. It ceases to be a Pending Item but never becomes a Chain Item.
402.3.a.: This is not an Ability being countered.
402.3.b.: If there are legal options to choose, the ability’s controller must choose them. They may not decline this stage of playing a Trigger.