Double any counters infinitely

Equipped creature has ": Add one mana of any color." Equip

, : Tap target creature and put a +1/+1 counter on it. Until end of turn, that creature gains ": Double the number of +1/+1 counters on this creature."

, : Double the number of each kind of counter on target permanent. ( is the untap symbol.)

Activated abilities of creatures you control cost less to activate. This effect can't reduce the mana in that cost to less than one mana.