Minecraft wiki entry for Entity_format, associated text: 1 Folder Structure
2 NBT Structure
3 Entity Format
3.1 Mobs
3.1.1 Axolotl color
3.1.2 Cat type
3.1.3 Collar color
3.1.4 Fox types
3.1.5 Frog variants
3.1.6 Variant
3.1.7 Mooshroom type
3.1.8 Genes
3.1.9 Parrot color
3.1.10 Rabbit Type
3.1.11 Sheep color
3.1.12 Shulker color
3.1.13 Color
3.1.14 Villager type
3.1.15 Villager profession
3.1.16 Collar color
3.1.17 Zombie villager type
3.1.18 Zombie villager profession
3.2 Projectiles
3.3 Items and XP Orbs
3.4 Vehicles
3.5 Dynamic tiles
3.6 Other
3.6.1 Disabled slots
4 History