Tournament Practice is the most competitive room in the Constructed Open Play area, it is where the most serious players go to test their best decks before entering them into a Constructed event
It's powerful that it doesn't even allow the activation of monster effects of monsters that have been Special Summoned, but many of his Decks start from Link Summons, and many of his Decks have 2500 RBI even without monster effects
These provide the base framework to what is allowed in VGC, such as all Pokmon being auto-leveled to level 50, or the Species and Item Clauses (you may not use the same Pokmon or items, respectively, more than once on your team)
Mason would not allow the player to attach a water energy card to the benched Staryu instead of the active Goldeen on turn one because doing so would change his script in two ways: Goldeen would not be able to attack on turn one and Seaking would not be able to use Waterfall on turn two
Until end of turn, whenever you play a land or cast a spell this way, its owner draws a card
