Add 1 Digimon card with [Kyubimon], [Taomon] or [Sakuyamon] in its name, and 1 [Rika Nonaka] or use cost 2 or higher Option card among them to the hand
One of the things to keep in mind when doing the draft is that you need both creatures and spells to make things work
Firstly, heres how its summoned: you can banish 3 monsters (either Light, Dark, or a mix of the two) to summon this card
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This means that every card thats legal in Commander can be used in your deck
The deck that Dorimon was built for was Alphamon, whose cards have many effects that add cards underneath themselves, but it is printed in a way that is still somewhat generic