Mana Manipulator Golem

{3}: Put a +1/+1 counter on Mana Manipulator
Golem.
Remove a +1/+1 counter from Mana Manipulator
Golem, add two mana of any combination to your
mana pool.
At the beginning of each players end step tap all
untaped lands that player controls then put that
many +1/+1 counters on Mana Manipulator
Golem.