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Q. Under the new Black & White rules, Supporters go to the Discard Pile when played. So does that mean that the part on Buck's Training which says "As long as Buck's Training is next to your Active Pokemon..." won't work any more?
A. Yes, it will still work. The intent is that the effect works during the turn when the Supporter was played. So even though Buck's Training is in the Discard Pile, each of your Active Pokemon's attacks does 10 more damage to the Active Pokemon. (Apr 28, 2011 PUI Rules Team)
Q. Say you played a Supporter this turn and recovered it to your hand with VS Seeker. Would you be able to use that Supporter for Jirachi's "Detour" attack or not?
A. Even though the Supporter is no longer in the Discard Pile, Detour can use its effect since it was played during the turn. (Apr 28, 2011 PUI Rules Team)