Indestructible is a static ability defined in CR 702.12. It means that the permanent is not destroyed by effects that say 'destroy' and is not destroyed by lethal damage (CR 702.12b). Sacrifice is an entirely different mechanism and is not destruction.
When a player sacrifices a permanent, they move it from the battlefield to their graveyard as a cost or as the result of an effect (CR 701.17). This action bypasses the 'destroy' step entirely, so indestructible offers no protection against it.
This distinction matters a great deal in gameplay. Effects like 'sacrifice a creature' on cards such as Diabolic Edict or Fleshmad Steed force a player to put a creature into the graveyard directly. No amount of indestructibility stops this, because the creature is never 'destroyed' — it is simply sacrificed.
Concrete example: You control a Darksteel Colossus (indestructible). Your opponent casts Cruel Edict, which reads 'target opponent sacrifices a creature.' You must sacrifice Darksteel Colossus; indestructible does nothing to prevent this because the card does not use the word 'destroy.'
Similarly, if a card's ability says 'sacrifice this creature' as an upkeep cost, an indestructible creature would still be sacrificed if the cost is not paid or the effect resolves. Only effects specifically using 'destroy' or dealing lethal damage are blocked by indestructible (CR 702.12b).
Unofficial fan resource — not affiliated with or endorsed by Wizards of the Coast. Answers are AI-generated estimates grounded in the Comprehensive Rules and are not a substitute for an official judge. Verify anything match-critical.