Evolutionary Escalation

Oracle Text

At the beginning of your upkeep, put three +1/+1 counters on target creature you control and three +1/+1 counters on target creature an opponent controls.

Card Rulings

11/8/2016 You choose two targets for Evolutionary Escalation’s ability as it’s put onto the stack. No player may cast spells or activate abilities during your turn before this happens.
11/8/2016 If there aren’t two legal targets for Evolutionary Escalation’s ability as it’s put onto the stack, it’s taken off the stack and no creature gets +1/+1 counters.
11/8/2016 If one target becomes illegal before Evolutionary Escalation’s ability resolves, you’ll put three +1/+1 counters on the target that’s still legal.