Magmatic Core
{2}{R}{R}
Enchantment
Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on ~this~, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
At the beginning of your end step, ~this~ deals X damage divided as you choose among any number of target creatures, where X is the number of age counters on it.