Indestructible is an evergreen keyword ability. Indestructible permanents can't be destroyed by rules or effects. Indestructible allows a card to ignore effects that say "destroy", such as "Destroy target artifact" or "Destroy all creatures", and instead remain on the battlefield rather than going to their owner's graveyard. It also allows creatures to ignore the amount of damage marked on them, even if that amount is greater than their toughness.
Indestructible only applies to permanents on the battlefield. They can also be removed from the battlefield by being bounced or exiled. The first card that conferred indestructibility was Consecrate Land in Alpha , followed by Guardian Beast in Arabian Nights , but no other cards followed and no formal rules existed until Darksteel.
In this way, it was just an attribute that some permanents had. Starting with Kaladesh , regeneration was retired.
Indestructible is primary in white , secondary in black and green, and tertiary in blue and red. Black and green, as the replacement for regeneration, often have activated abilities that grant indestructible until end of turn.
White will at times use temporary indestructibility where it used to use protection. Ikoria Commander introduced indestructible counters. Removing indestructible is a newer, rarely-seen ability, primarily given to red, as its damage-based removal translates poorly to exile effects.
