Say my opponent used Turtonator GX's "Shell Trap" attack last turn, then on my turn I attack it with Shaymin EX's "Sky Return" attack. What happens to the 8 damage counters effect from "Shell Trap"?
Sky Return puts Shaymin EX into the hand as part of its attack before the damage counters are placed for Shell Trap's effect.
Source: TPCi Rules Team (2017-06-08)