Minecraft wiki entry for ED, associated text: Entity data
Additional fields for mobs that can breed[show]
Tags common to all entities[show]
Tags common to all mobs[show]
Tags common to all horses[show]
 SkeletonTrap: 1 or 0 (true/false) - true if the horse is a trapped skeleton horse. Does not affect horse type.
 SkeletonTrapTime: Incremented each tick when SkeletonTrap is set to 1. The horse automatically despawns when it reaches 18000 (15 minutes).