They look as follows (the dagger marks signifying the fact that it is impossible to tell the beginning and end of the sequences): Nidoran m, Diglett, Abra, Fire Energy, Starmie, Ponyta, Fighting Energy, Koffing, Pikachu, Doduo, Fire Energy, Gust of Wind, Machop, Lightning Energy, Gastly, Ponyta, Tangela, Grass Energy, Squirtle, Voltorb, Psychic Energy, Sandshrew, Weedle, Rattata, Water Energy, Drowzee, Poliwag, Fighting Energy, Charmander, Potion, Onix, Lightning Energy, Koffing, Magnemite, Psychic Energy, Pidgey, Abra, Metapod, Water Energy, Diglett, Staryu, Fighting Energy, Caterpie, Switch, Vulpix, Fire Energy, Voltorb, Machop, Grass Energy, Poliwag, Nidoran m, Rattata, Lightning Energy, Gastly, Doduo, Psychic Energy, Tangela, Sandshrew, Bill, Fighting Energy, Vulpix, Squirtle, Fire Energy, Pikachu, Bulbasaur, Drowzee, Grass Energy, Onix, Pidgey, Lightning Energy, Staryu, Charmander, Metapod, Psychic Energy, Energy Removal, Magnemite, Water Energy Poliwhirl, Maintenance, Farfetchd, Ivysaur, Pokmon Center, Machoke, Jynx, Full Heal, Kakuna, Double Colorless Energy, Porygon, Charmeleon, Maintenance, Poliwhirl, Raticate, Pokdex, Nidorino, Magikarp, Professor Oak, Magmar, Pokmon Flute, Porygon, Haunter, Energy Retrieval, Seel, Dratini, Double Colorless Energy, Growlithe, Wartortle, Full Heal, Dewgong, Defender, Kakuna, Magmar, Pokmon Center, Raticate, Seel, Revive, Nidorino, Kadabra, PlusPower, Dewgong, Super Potion, Arcanine The length of the sequences (77 and 44) which add up to 121 cards are too much of a coincidence to assume anything other than that they were printed on one single sheet and then separated before being inserted into packs

Legality depends on the tournament format -- Thunder Dragondark can be legal in some formats and banned or restricted in others
Proper display is about preserving your collection while enjoying it
Yellow Border - WOTC Style - Cosmos Holo image19203212 985 KB I have heard rumors these Filler Cards originated from WOTC employees