This card was reprinted in the Base Set 2 reprint set, which was only released outside of Japan. In Japan, it was later included in the Totodile Side Deck of the Neo Introduction Set. It was later reprinted in the Undaunted expansion with new artwork by Ryo Ueda and updated text. This print now specifically states that only damage by an opponent's attack is reduced, preventing the use of this card in tandem with Pokémon that have attacks with recoil damage.
Trivia
Origin
Defender is the Japanese name of X Defend, an item in the Pokémon games. The Japanese name of the item was either used for the English card by mistake, or was intentionally used as 'Defender' is inscribed on the side of the object in the card's original artwork.