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Imagine you and your child are battling with Pikachu and Bulbasaur
You can go wild and play 2-Headed Giant matches, try to draft a Commander deck or build multiple decks from the same card pool
The downsides are that its not a plant, and that it forces you to run extra Stardust Dragons, which isnt terrible
Once the rules of the real card game were pinned down, the Battle City arc adopted these rules under the premise of changes Kaiba made personally (most notably the need to sacrifice low level monsters in order to summon high level monsters, otherwise no reason to not stack your deck with the beefiest monsters you can get your hands on)
destroy as many monsters on the field as possible, then each player banishes all monsters from their Deck, face-down, then you can Special Summon 1 Normal Monster from your GY