Nuclear weapons developement

This card enters the game with X "development" counters on it.
{t}{3}: add 2 "development" counters to this card
{t}{5}: Retire six counters from this card, destroy
target land, deal 5 damage to its owner, and all
the creatures that player conrols get -1/-2.
Each time this card destroys a land, all
Radioactive creatures get +1/+0.