Check copyright date accuracy
Among the important signs there is the inscription "Edition" and the date of printing no later than February 16, 1999
Starting with a mechanic idea, it felt straightforward to create some cards with the mechanic and/or that supported the mechanic, then add some generic cards like removal spells and simple creatures
CP1 - 1P - 2/1 [new mechanic A] (a two mana purple card is tough to play in limited, so I think it should be good) CP2 - 2P - 3/1 First Strike CP3 - 2P - 2/2 [new mechanic B] CP4 - 3P - 2/2 Flying, [new mechanic B] CP5 - 4P - 4/3 [new mechanic B] CP6 - 5P - 4/6 Trample CP7 - P - Instant - Remove Soul CP8 - 1P - Instant - Choose one: counter target green spell, or destroy target green permanent, or destroy target forest (this would be a cycle of six, so it needs to be different from the existing R/U blasts) CP9 - 2P - Sorcery - Deal 3 damage to target creature or player
This allowed for new and different decks to emerge, though the winner was the Eldrazi Deck
You don't get to keep them for later