Opponents creatures get 4 -1/-1 counters per turn

Enchant player At the beginning of enchanted player's first upkeep each turn, that player gets an additional upkeep step after this step.

At the beginning of your upkeep, put a -1/-1 counter on each creature.

At the beginning of your upkeep, remove a -1/-1 counter from each creature you control. Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)