Can Thrill of the Hunt with Brynhildr Thundersong counter Dazzling Aurora?

To answer your question: No, Thrill of the Hunt (using Brynhir Thundersong) does not "counter" Dazzling Aurora in the game's rules sense, but playing it in response can effectively prevent the opponent from using the unit played by Dazzling Aurora.

The Interaction

• Dazzling Aurora is a Gear with a triggered ability that occurs at the end of the turn.
• Thrill of the Hunt is a [Reaction] spell. You can play it on the chain in response to the Dazzling Aurora trigger.
• Brynhir Thundersong has a "When you play me" triggered ability that prevents opponents from playing cards for the rest of the turn once it resolves.

The Sequence

1. Dazzling Aurora triggers: The ability is placed on the chain.
2. You play Thrill of the Hunt: You target your Brynhir Thundersong to banish and re-play her. Thrill of the Hunt is placed on top of the chain.
3. Chain resolves (LIFO):
   • Thrill of the Hunt resolves first: You banish Brynhir and play her to a battlefield.
   • Brynhir's Trigger: Because she was just played, her "When you play me" ability is placed on the chain.
   • Brynhir's Trigger resolves: This effect takes hold, preventing opponents from playing cards (including those played via card effects) for the remainder of the turn.
   • Dazzling Aurora resolves: The Dazzling Aurora effect executes. It reveals cards and attempts to play the revealed unit. However, because Brynhir's effect is now active, the opponent is forbidden from playing that unit.

Key Clarifications

• "Counter" vs. "Prevent": In Riftbound, "Counter" (Rule 425) is a specific action that negates a card or ability on the chain. Thrill of the Hunt does not counter Dazzling Aurora; it simply creates a game state where the opponent is legally restricted from completing the Dazzling Aurora effect.
• Restriction on Play: According to RiftJudge FAQ #10332, because playing a unit via a card effect (like Dazzling Aurora) counts as "playing a card," Brynhir's ability successfully prevents the opponent from playing the unit revealed by Dazzling Aurora.
• Timing: You must have Brynhir available (on the board or in hand) to use Thrill of the Hunt in this manner. You are reacting to the Dazzling Aurora trigger before it resolves.