Whenever a creature enters the battlefield under your control, and no other creatures that share a type with it, you create a token thats a copy of that creature
Or maybe you just want to regulate with Urza's Law
A lot of mana dorks are very budget-friendly these days, too, with classics like Llanowar Elves and Elvish Mystic available as low as $0.20 and $0.30, respectively
They are pretty common custom novelties that you can find across the internet
There is currently a seller on eBay offering the entire 20card collection in PSA 10 , which is extraordinary due to how hard it is to find fews: Card Types & Identification Aside from the PR (Promotional) cards, the game utilizes two primary types: CH (Character) units for battle and TE (Technique) cards for special moves
But like the devious creatures and beguiling magic that lurk among the shadows, this world is not all that it seems