Minecraft wiki entry for Entity_format, associated text: : The entity's root tag.
 Invul: The number of ticks of invulnerability left after being initially created. 0 once invulnerability has expired.[needs testing]
 AirAttack: Unknown.
 ShieldHealth: Unknown.
 Phase: Unknown.
 SpawningFrames: Unknown.
 maxHealth: Unknown.
 lastHealthInterval: Unknown.
 dyingFrames: Unknown.
 overlayAlpha: Unknown.
 swellAmount: Unknown.
 oldSwellAmount: Unknown.
 firerate: Unknown.