POP Series 7

Pokémon POP Series 7 was the seventh series of Special Edition sets released by Nintendo which featured Pokémon cards. It was released on March 18th, 2005 and featured the first cards of the Delta Species, a hybrid population of common Pokémon changed into new species by the effect of a mysterious energy. Delta Species Pokémon are identifiable by their angled Pokédex markings and have special Poké-Powers that put them in a class by themselves.

POP Series 7 also marked the introduction of a new type of card called Pokémon ex, denoted by a bronze border. Pokémon ex were not only stronger than the usual cards but also featured a special rule called the Knock Out Rule in which when a Pokémon ex was Knocked Out, the opponent would take 2 prize cards instead of the usual one, making them even more powerful.