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Double Team is the down special move of Lucario in the Super Smash Bros. series, starting in Super Smash Bros. Brawl. When the attack is used, Lucario stands on one leg and split into two copies of himself. This, however, does not do any damage unless an opposing player performs any sort of attack on him shortly after the move is used, in which case Lucario disappears, reappears behind the attacker, and slide kicks into them, countering the move. However, it only works if the attack is used just before being attacked, as it will not work if kept in action for too long. The power of the counter attack is increased according to the damage Lucario has taken. Using the move in the air briefly slows his descent.
In Super Smash Bros. for Nintendo 3DS / Wii U, Double Team has two variants: Glancing Counter and Stunning Double Team. Glancing Counter deals less damage and knockback, but still lets Lucario attack even if he is not attacked in return, while Stunning Double Team replaces his slide kick with a teleport, making him discharge electricity that stuns nearly opponents and deal minor damage.