Other Cells gather to aid when its HP becomes half or less. Then the Pokémon changes its form to Complete Forme.
Effect
When this Pokémon's HP drops to 50% or less, it changes form into Complete Forme and gains HP equal to the difference between its old maximum HP and its new maximum HP. This Pokémon remains in Complete Forme until the battle ends, at which point it is also fully healed.
If this Pokémon's type was changed during battle, it reverts to Dragon/Ground when this ability activates.
This Pokémon returns to Standard Mode upon leaving battle or losing this ability. This ability will not activate if this Pokémon is not a Zygarde in either 10% or 50% form.