Expedition Base Set: How to Identify Cards From This Set

• This was the first set to introduce Nintendo's e-Reader Dot Code technology, which is why the card border is noticeably wider
• The dot code let players use an e-Reader device to view Pokédex data, play a minigame, play music, or activate a hidden attack
• The left side of the artwork window became rounded — a straightforward visual cue that distinguishes this set from earlier WOTC sets
• A unique ID number was added below the artwork window, while the traditional Pokédex description text was removed
• The illustrator credit moved to the bottom center of the card

This was one of the last sets released by Wizards of the Coast, and marked the start of the 'Pokémon-e' card design (wide border + dot code); Aquapolis and Skyridge later followed the same design language. All three can be told apart by total card count (165/165 vs. 186/186 vs. 182/182), but no verbatim source describing the specific set-symbol differences was found, so they are not listed under commonly_confused_with.

• Bottom-left or bottom-right corner: the set symbol and the collector number (e.g. 4/102) tell you the set; older cards have no symbol at all, which itself narrows them to Base Set.
• Left of the number: a 1st Edition stamp, if present, sits below the art on WOTC-era cards.
• Regulation mark (a letter in a box near the bottom, D through H so far) dates modern cards to a two-year window.
• Back of the card: the blue Poké Ball back has changed little since 1999; a washed-out, blurry or wrongly colored back is the first sign of a fake.

Lay the card flat on a dark surface in daylight, straight on, with the whole card in frame, then a close-up of the bottom edge where the set symbol, number and any edition stamp sit. Tilt holo cards under the light for a second shot to show the foil pattern. Photograph the back too. The app reads the card and set; the edition and rarity checks above tell you which version you have.