Proteans, Primordium Incarnate

Flying, Trample, Indestructible
Each upkeep, roll a six-sided die, then roll dice
equal to that result. For each die, put a 0/0
incarnation creature token named Protean onto
the battlefield of a random color with +1/+1
counters equal to its result.
Each time you roll 4 or greater on a die,
proliferate.