At the beginning of your end step, if a land entered the battlefield under your control this turn and you control a prime number of lands, create Primo, the Indivisible, a legendary 0/0 green and blue Fractal creature token, then put that many +1/+1 counters on it. (2, 3, 5, 7, 11, 13, 17, 19, 23, 29, and 31 are prime numbers.)
There are a few more prime numbers, but we couldn't fit them all on the card. (Some of them would take up more room than we have in the text box by themselves, but you probably won't control that many lands.)
20 Sept 2024
If you don't control a prime number of lands as Zimone's ability tries to resolve, it won't resolve.
20 Sept 2024
In case you do end up with more than 31 lands, the remaining prime numbers below 100 are 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, and 97.
20 Sept 2024
If a land hasn't entered the battlefield under your control during your turn by the time your end step begins, Zimone's ability won't trigger at all. You won't be able to put a land onto the battlefield under your control during your end step in time to have the ability trigger.