What it does
Indestructible means a permanent can't be destroyed. Specifically, it ignores effects that say "destroy," and it can't be destroyed by lethal damage (damage marked equal to or greater than its toughness). It's an immunity, not a buff—the permanent still has its normal stats.
The big nuance: indestructible doesn't make something invincible. It still dies to "sacrifice" effects, "exile" effects, having toughness reduced to 0 (a state-based check, not destruction), or losing all toughness via -X/-X effects. It can also be bounced, stolen, or countered as it isn't even on the battlefield yet. Indestructible creatures with 0 toughness still die immediately.
In Commander, it matters constantly—board wipes like Wrath of God and Damnation are everywhere, so indestructibility shines for protecting key creatures and commanders. Smart players answer it with edicts, exile, or Toxic Deluge-style -X/-X wipes instead.













