Wizards of the Coast is by far of the most popular era. Before their contract ended for Pokémon card production, the E-Reader was introduced for Gameboy. The cards made in this era basically had a QR code on the bottom, which allowed them to be swiped. The Pokémon that was on the card with them become a character that you had in the game. This also caused a lot of unnecessary damage with these cards from swiping them which led to considerably lower populations for high grade high-end cards. WOTC wanted to create the best cards that they had ever made since this was their last opportunity to leave an impression. The final three WOTC sets to this day are some of the absolute most desirable. These include Expedition, Aquapolis and Skyridge. Every single card in this series is a PSA 10 Holo from one of these three sets. We have also included reverse holos since they typically have even lower populations than the holos. Many of them will have PSA 10 populations in the single digits. About 70% of the most valuable WOTC cards are from one of these E-Series sets.