>>19594002The game decides who goes first before any Pokémon Mega Evolves
If a Pokémon gains or loses speed as a result of Mega Evolving, they still move based on the speed of their base form
If Sableye uses a status move, Prankster will set it priority to +1 that turn, then it will Mega Evolve and use the status move first in the +1 priority bracket