If a creature has indestructible and is dealt damage equal to its toughness, does it die?

Normally, a creature dies when state-based actions (SBAs) are checked and it has damage marked on it equal to or greater than its toughness — this is the definition of lethal damage under CR 704.5g. However, indestructible modifies this outcome.

Under CR 702.12b, a permanent with indestructible can't be destroyed. CR 704.5g specifies that a creature with lethal damage marked on it is destroyed, but since indestructible prevents destruction, the creature simply remains on the battlefield with the damage marked on it. The SBA is checked, the game recognizes the damage is lethal, but the destruction effect never resolves.

The damage itself still exists on the creature — it's marked there until end of turn (or until removed). If somehow the creature loses indestructible later in the same turn, and the damage is still marked, SBAs would then check again and the creature would die at that point.

Concrete example: Your opponent controls a 4/4 creature with indestructible. You attack with a 5/5 and they block. Both creatures take lethal damage. Your 5/5 dies (704.5g), but their 4/4 stays on the battlefield because indestructible shields it from being destroyed (702.12b).

Note: Indestructible does NOT protect against effects that say "exile" or "sacrifice," nor does it prevent -1/-1 counters or toughness reduction from killing a creature — those are not destruction effects.