Pauper is a Pokemon TCG format that allows cards that have a Common or Uncommon rarity printing. (Note: this is different from Pauper in Magic the Gathering where the only allowed rarity is Common.)
You can then add additional restraints around it: which sets are allowed (a lot of people seem to play Pauper as Black and White on format) and which cards are banned but the baseline is the rarity. Other rules of deck building and gameplay are the same.
You’re allowed to play any version of a card, as long as it has a legal Common/Uncommon printing within the legal sets. A great example of this is Professor’s Research which has had Common, Uncommon, Rare , Ultra Rare and Promo printings. Any of these is allowed to be played.
An example of BW-on banlist from JustInBasil’s website is:
- Ambipom PGO 57
- Bunnelby PRC 121
- Chip-Chip Ice Axe UNB 165
- Cryogonal UNM 46
- Delinquent BKP 98
- Dusclops SFA 19
- Flabébé FLI 83
- Forest of Giant Plants AOR 74
- Hex Maniac AOR 75
- Lt. Surge’s Strategy UNB 178
- Lunatone PGO 34
- Lysandre’s Trump Card PHF 99
- Oranguru UPR 114
- Puzzle of Time BKP 109
- Red Card XY 124
- Reset Stamp UNM 206
- Sableye DEX 62
- Shinx UPR 45
Since the format is not sanctioned and there’s no definite rule set or rules committee, it’s good to clarify the used ruleset before starting deck building and attending events.
If you’re looking for ideas for decklists, Control Players Unite organises Pauper tournaments and share results and decklists in Limitless TCG. They play with cards from Standard only as the games are played in Live which doesn’t have all expanded cards and they have their own banlist:
- Pecharunt w/the Toxic Subjugation ability (an oft-used promo rare)
- Hop’s Choice Band
- Postwick
- Festival Lead Dipplin
- Festival Lead Goldeen
- Festival Lead Seaking
- Festival Lead Swirlix