Along with the strong Pokemon, Mythical Islands also introduced some new item cards in Pokemon Pocket
This card does come with the added bonus of denying your opponent's ability to activate spells and trap cards until the second turn after The Wicked Avatar has been played
And to top it all off, theres a spin-dial lore counter to easily track your journey to victory
However, as an attack lock, there are many holes, and as it has already been said, Marshmallow itself is an effect that is activated in reverse, so it has a bad compatibility with this card, and its low stats make it vulnerable to penetration
In moving forward, it would probably be a good idea for you to have an idea of what's the ideal end state for your archetype