They could do almost anything: they might deal damage to Pokmon on the enemy bench, deal extra damage if you win a coin flip, force you to discard Energy from the Pokmon that made the attack anything
Cosmos Channelling X SPELL Continuous You can send 1 monster you control that is owned by your opponent to the GY
Both players took a controlling role, but you did so knowing they have excess removal in their deck, while you have planeswalkers and card advantage
Then, your opponent draws 1 card
While most local tournaments give competitors a structured environment to play in with small prizes at stake, the majority of Duelists who attend are there to hang out, chat, and casually face off against people with a common interest in the YuGiOh
The Trading Card Game even branched out with a board game edition to help younguns learn the ways of play