
All other stat changes and type changes of a Mega Evolution will take effect immediately and damage calculation will proceed as usual. However, turn order will be determined normally on every turn afterwards. The opposite is also true for Pokémon who lose Speed from Mega Evolution, such as Garchomp. Performing Mega Evolution will not alter the turn order, so a Pokémon with a lower Speed than their opponent will still go after them on the one turn the Mega Evolution occurs, even if their Mega Evolution increases Speed and would otherwise cause them to go first. Neither volatile nor non-volatile status conditions such as paralysis, sleep, and infatuation will have any effect over a Pokémon's ability to Mega Evolve even if they result in the Pokémon not being able to move that turn, the Mega Evolution will occur regardless. Likewise, Mega Stones also cannot be given to or taken by their respective species using any of the aforementioned moves or Abilities. Using Knock Off against a Pokémon holding its respective Mega Stone will not remove the item, nor will Knock Off's added effect of increased power on the turn it removes an item be granted. Embargo and Magic Room also have no effect, and will not prevent a Pokémon from using its Mega Stone to Mega Evolve. If used by the holder, moves such as Bestow, Fling, Trick and Switcheroo will always fail.

Abilities such as Magician and Pickpocket will fail to snatch the Mega Stone from its holder and Pokémon with Klutz are able to use their respective Mega Stone. Mega Stones cannot be taken via Thief, Covet, Trick, or Switcheroo.

Trainers on the same team during a Multi Battle will each be able to Mega Evolve once during the battle. If a Mega Evolved Pokémon faints, but is later revived, that Pokémon cannot obtain a Mega Evolved state again for the remaining duration of the battle. A Mega Evolved Pokémon can only revert back to its original state upon fainting or the conclusion of the battle. Switching the Mega Evolved Pokémon out will not dissolve a Mega Evolution.

Once per battle, only a single Pokémon for each Trainer may Mega Evolve. In order to Mega Evolve, the Pokémon must be holding the appropriate Mega Stones (with the exception of Rayquaza which is only required to know the move Dragon Ascent).
