Doesn't compile yet. CraftBukkit Changes: 90d6905b Repackage NMS 69cf961d Repackage patches Spigot Changes: 79d53c28 Repackage NMS
Crystals can end up in a bad state in certain conditions which causes an exception on the expected number of crystals going negative. This ensures the crystals/pillars are in expected state when the dragon spawns.