14 Apr 2023
If another effect modifies how much damage a source would deal, including preventing some of it, the player being dealt damage or the controller of the permanent being dealt damage chooses an order in which to apply those effects. If all of the damage is prevented, Rankle and Torbran’s effect no longer applies.
14 Apr 2023
The additional 2 damage is dealt by the same source as the original source of damage. The damage isn’t dealt by Rankle and Torbran unless Rankle and Torbran is the original source of damage.
14 Apr 2023
To resolve the second mode, starting with you (or, in unusual cases, the player whose turn it is if not you) and proceeding in turn order, each player chooses a creature they control to sacrifice. Then those creatures are sacrificed at the same time.
14 Apr 2023
You may choose none of the modes, some of them, or all of them. Any modes chosen will happen in order.