Minecraft's abstract entity class (which is inherited in all entities) holds attributes that are not shared in Core Shaders:
FireTicks, FreezeTicks, Coordinates/Location, Passengers (this could be expressed in a number such as the number of passengers), Lifespan/TicksLived, if its custom name is visible, if it's glowing, their glowing color, if it's riding an entity, if it's invulnerable, if it's in water, if it's on the ground, if it's silent, etc.