Kingsport Lighthouse

At the beginning of each players upkeep, if they control no creatures with radiation counters on
them. Each opponent loses 2 life and you gain
life equal to the total life lost this way.
{t}: Add {w/b}{w/b} to your mana pool, you lose 1 life.
As long as Kingsport Lighthouse is a capital, you
may distribute or remove any number of
radiation counters on creatures you control.
(Anytime you could cast an instant.)