In Commander, does commander damage reset if your commander dies and is recast?

Commander damage is tracked as a running total for the whole game. According to the Commander rules (which supplement the Comprehensive Rules), damage dealt by a commander to a player is tracked cumulatively regardless of how many times that commander has changed zones, been recast, or returned from the command zone.

This means if your commander deals 10 combat damage to a player in one game, then dies and is recast, any future combat damage it deals to that same player adds on top of those original 10 points. Once a player has taken 21 or more combat damage from a single commander over the course of the game, they lose (CR 903.10a).

The key principle here is that the 'commander damage' loss condition is specifically designed to be cumulative across the entire game, making commanders with repeated recursion still dangerous over time. The zone-change tracking inherent to commanders (CR 903.9) is what enables this — the game always knows which object is your commander no matter where it goes.

Concrete example: Your Rafiq of the Many deals 15 combat damage to an opponent, then is destroyed and sent to the command zone. You pay the commander tax and recast it. Rafiq later deals 7 more combat damage to that same opponent. The total is 22 — that opponent loses the game, even though Rafiq 'died' in between.

There is no game mechanic that resets commander damage. Even if the commander somehow became a different object temporarily, the Commander format rules explicitly preserve this cumulative tracking for the duration of the game (CR 903.10a, 903.9).