Primordial Hydra (Duels of the Planeswalkers Promos) [Duels of the Planeswalkers Promos 2013]

Primordial Hydra enters the battlefield with X +1/+1 counters on it.
At the beginning of your upkeep, double the number of +1/+1 counters on Primordial Hydra.
Primordial Hydra has trample as long as it has ten or more +1/+1 counters on it.