In battle
Generation III to IV
Synchronize passes on status problems to the opponent that caused the problem. Synchronize will not pass on the Sleep or Frozen status conditions, or if the status condition was obtained from items such as the Flame Orb. Synchronize will have no effect if the other Pokémon has a type or Ability that prevents them from being Poisoned, Paralyzed, or Burned. The badly poisoned condition is passed on as regular poison.
Generation V
Synchronize now passes the badly poisoned condition on as bad poison, rather than normal poison.
If Psycho Shift is used, Synchronize activates before Psycho Shift cures the user of status. Therefore, Synchronize will fail to reflect status conditions when Psycho Shift is used.
Outside of battle
From Pokémon Emerald onwards, if a Pokémon with this Ability is leading the party, there is a 50% chance that wild Pokémon encountered will have the same Nature as the Pokémon with Synchronize. This does not apply to roaming or gift Pokémon. In Emerald, it did not apply to stationary Pokémon either, such as Regirock or Rayquaza.
The Ability is nullified when a Pokémon with Synchronize is strolling in the Pokéwalker or when capturing Dream World Pokémon from the Entree Forest.
