Increasing Vengeance

Each of the copies will have the same targets as the spell it's copying unless you choose new ones. You may change any number of the targets, including all of them or none of them. If, for one of the targets, you can't choose a new legal target, then it remains unchanged (even if the current target is illegal). If there are two copies, you may change the targets of each of them to different legal targets.

You can't choose to pay any additional costs for the copies. However, effects based on any additional costs that were paid for the original spell are copied as though those same costs were paid for the copies too. For example, if you sacrifice a 3/3 creature to cast Fling and then copy it with Increasing Vengeance, the copies of Fling will also deal 3 damage to its target.

Increasing Vengeance can target (and copy) any instant or sorcery spell you control, not just one with targets.