What happens if my opponent plays Piercing Light repeatedly, but I react with Thrill of the Hunt and target his first target?

To resolve the interaction between Piercing Light (with Repeat) and Thrill of the Hunt, we apply the game's "Do As Much As You Can" (DAMAYC) logic. When the first target of Piercing Light is banished and re-played via Thrill of the Hunt, it becomes a new game object, rendering the original targeting attempt invalid.

Sequence of Events

1. Playing the Spell: The opponent plays Piercing Light with the Repeat cost paid. They declare two targets for the first instance of damage and two targets for the second instance (total of four potential targets).
2. Reaction: You play Thrill of the Hunt as a [Reaction], targeting the unit chosen for the first damage instance.
3. Chain Resolves (LIFO):
   • Thrill of the Hunt resolves first: The unit is banished and re-played. It is now a new game object.
   • Piercing Light resolves (First Instance): The spell attempts to deal 2 damage to the first target. Because that unit is now a different game object than the one targeted when the spell was played, the damage instruction fails for that target. The spell proceeds to the second target, which takes 2 damage if it remains a legal target.
   • Piercing Light resolves (Repeated Instance): The spell repeats the process. Again, the instruction to damage the original first target fails, and the spell attempts to deal 2 damage to the second target.

Key Rules

• "Then" is not a condition: As noted in RiftJudge FAQ #1623, #6726, and #8840, "then" is a timing instruction. The failure of the first damage instruction does not prevent the spell from attempting the subsequent damage instruction.
• DAMAYC (Do As Much As You Can): Per Rule 359.3.e.11, instructions are followed as much as possible. Even if one target is no longer legal, the spell continues to resolve any remaining valid instructions.
• Illegal Targets: Per Rule 359.3.e.1, a spell continues to resolve even if some of its targets become illegal or change state (e.g., leaving the battlefield and returning as a new object).

Note: I could not fully verify this ruling against the retrieved rules.