Minecraft wiki entry for Entity_format, associated text: : The entity's root tag.
 Duration: The maximum age of the field.
 ReapplicationDelay: The number of ticks before reapplying the effect.
 DurationOnUse: The amount the duration of the field changes upon applying the effect.
 InitialRadius: The field's initial radius.
 RadiusOnUse: The amount the radius changes upon applying the effect. Normally negative.
 RadiusPerTick: The amount the radius changes per tick. Normally negative.
 Radius: The field's current radius.
 OwnerId: The Unique ID of the entity who created the cloud. If it has no owner, defaults to -1.
 PotionId: The name of the default potion effect. See potion data values for valid IDs.
 ParticleId: The particles displayed by the field.
 ParticleColor: The color of the particles.
 mobEffects: A list of the applied effects.
Tags common to mob effect[show]
 SpawnTick: The time when it was spawned.
 RadiusChangeOnPickup: The amount the radius changes when picked up by a glass bottle.
 PickupCount: How many dragon's breath can be picked up.