Vulnerable Crystals

In large or heavily modded Minecraft packs, End Crystals can occasionally become permanently invulnerable—effectively unbreakable—continuously healing or even resummoning the Ender Dragon, disrupting intended gameplay.

When this occurs, the typical workaround is to manually run a command such as:
/data modify entity @e[type=minecraft:end_crystal] Invulnerable set value 0

This datapack ensures that End Crystals remain vulnerable at all times, removing the need to run commands whenever the issue arises and allowing all Ender Dragon (re)encounters to proceed as intended.