Elspeth, Knight-Errant — ruling 1

Lethal damage and effects that say “destroy” won’t cause a permanent with indestructible to be put into the graveyard. However, a permanent with indestructible can be put into the graveyard for a number of reasons. The most likely reasons are if it’s sacrificed, if it’s a creature whose toughness is 0 or less, or if it’s an Aura that’s either unattached or attached to something illegal.

Elspeth, Knight-Errant — ruling 2

Emblems behave similarly to enchantments: They have an ability that, in a general sense, continually affects the game. The primary difference between them is that emblems aren’t permanents and don’t exist on the battlefield. Nothing in the game can remove an emblem, simply because no other spell or ability references them. Once you get an emblem, you keep it for the rest of the game. Emblems have no color, name, card type, or other characteristics beyond the listed ability.

Elspeth, Knight-Errant : règles, fonctionnement et interactions (MTG)

Elspeth, Knight-Errant is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

+1: Create a 1/1 white Soldier creature token. +1: Target creature gets +3/+3 and gains flying until end of turn. −8: You get an emblem with "Artifacts, creatures, enchantments, and lands you control have indestructible."

How it works : Elspeth, Knight-Errant

Original English text — Wizards of the Coast / Scryfall

#1July 1, 2013· Wizards of the Coast
Lethal damage and effects that say “destroy” won’t cause a permanent with indestructible to be put into the graveyard. However, a permanent with indestructible can be put into the graveyard for a number of reasons. The most likely reasons are if it’s sacrificed, if it’s a creature whose toughness is 0 or less, or if it’s an Aura that’s either unattached or attached to something illegal.
No other card is named in this ruling.
#2January 1, 2011· Wizards of the Coast
Emblems behave similarly to enchantments: They have an ability that, in a general sense, continually affects the game. The primary difference between them is that emblems aren’t permanents and don’t exist on the battlefield. Nothing in the game can remove an emblem, simply because no other spell or ability references them. Once you get an emblem, you keep it for the rest of the game. Emblems have no color, name, card type, or other characteristics beyond the listed ability.
No other card is named in this ruling.