If held by a Venusaur (or is present in the player's Bag)PE, allows it to Mega Evolve into Mega Venusaur if its Trainer has a Key Stone. Each Trainer can only Mega Evolve one Pokémon per battle.
Unaffected by item negating effects (such as Embargo and Klutz). Item manipulating effects (such as Trick and Fling) cannot give Venusaur a Venusaurite or remove a Venusaurite from Venusaur.
Outside of battle
If held by a Venusaur, allows it to Mega Evolve into Mega Venusaur when it performs a Spectacular Talent during a Pokémon Contest Spectacular while its Trainer has a Key Stone. Venusaur will remain a Mega Venusaur until the Talent Round ends.
The player can obtain the Venusaurite by completing Mission Card 15.
The Venusaurite was also available as a prize during the Mega Venusaur Competitive Stage. This Competitive Stage ran on the Nintendo 3DS version from May 29 to June 8, 2015, and August 24 to 31, 2015. It ran on the Pokémon Shuffle Mobile from February 23 to March 1, 2016.
The Venusaurite enables the following Mega Evolutions:
A Venusaurite belonging to a Trainer appeared in Mega Evolution Special IV, during the ten-battle gauntlet Lysandre had arranged for Alain's training. The Venusaurite is located on a band placed around the flower on Venusaur's back.
