The V Wave is a new feature that opens up when Victini arrives in Pokémon Paradise which is the main town in the game.
This feature randomly chooses a type of Pokemon, such as Grass, Poison and Fire etc ,each in-game day, and on the type chosen, the strength of moves is increases and the cost of Pokemon Points is decreased for all moves of the corresponding type.
You can, however, control the V Wave by using Victini's V-Roulette in Pokémon Paradise. By putting money into the roulette, you can increase the chances of the roulette landing on Victini which then allows you to select the Pokemon of your chossing.
