1999 Pokemon Base Set Booster Pack Black Triangle Error Blastoise Art PSA 8 on Fanatics Collect 1999 Base Set Black Triangle Error Booster Pack Set PSA 10 The very first expansion to be released for the Pokmon TCG was Base Set (Expansion Pack in Japan), and in front 1999 Pokemon Card Game (TCG) BASE SET Black Triangle Error Stamped EMPTY Packs eBay Just found this unopened error black triangle pack in my old card collection. Was considering getting it graded but was curious if anyone could explain what the difference is between a PSA A SEALED POKEMON BASE SET BLACK TRIANGLE ERROR PRINTED BOOST (1) HEAVY BLACK TRIANGLE Base Set Booster Pack (GUARANTEED HOLO)