Double Team
In Lucario's Double Team, Lucario performs a defensive tai chi-like action. If it is attacked during this animation, it teleports behind it's opponent and strikes them. It deals 7% to 15% damage and has a good amount of vertical knockback, depending on Lucario's percentage when it counters. This special requires fairly good timing as the lag time is as long as or even longer then the counter time. Also, if Lucario counters near the edge, it may teleport behind the attacker and slide off the edge.
Double Team is a Pokémon move, and is described as creating after images of one's self in order to raise evasiveness. In the anime, it is widely used to confuse the characters, as the illusions appear to move independent of the original pokemon. The illusions normally disappear upon contact, but in the seventh Pokemon movie, a Deoxys created copies of itself capable of carrying people and Pokemon. They could, however, be repelled by fairly weak attacks. Since moves like this are based on luck and just make it more likely for your opponent's attacks to miss, the Evasion Clause was created for tournaments. When in effect, the rule bans all moves that decrease accuracy or increase evasiveness.