Your search for "Swamp 306" revealed the following:
Swamp (586) - Retro Frame (30A) from 30th Anniversary Edition, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Dan Frazier Card Text:This version of this card has a non-standard Magic back. It is not legal for constructed play....
Swamp (003) - Arena League Promo 2006 (PAL06) from Arena League 2006, available at 401 Games Canada. Rarity: Rare Finish: Normal Artist: John Avon
Swamp (301) (CMA) from Commander Anthology, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Jung Park
Swamp (302) (FIN) from Final Fantasy, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Sean Vo
Swamp (587) - Retro Frame (30A) from 30th Anniversary Edition, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Dan Frazier Card Text:This version of this card has a non-standard Magic back. It is not legal for constructed play....
Swamp (300) (Foil) (FIN) from Final Fantasy, available at 401 Games Canada. Rarity: Common Finish: Foil Artist: Domenico Cava
Swamp (301) (Foil) (FIN) from Final Fantasy, available at 401 Games Canada. Rarity: Common Finish: Foil Artist: Fang Xinyu
Swamp (296) (CEI) from Intl. Collectors’ Edition, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Dan Frazier Card Text:(This card has square corners and a gold bordered back. Not tournament legal.)Tap to add B to your mana pool....
Swamp (588) - Retro Frame (30A) from 30th Anniversary Edition, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Dan Frazier Card Text:This version of this card has a non-standard Magic back. It is not legal for constructed play....
Swamp (290) (30A) from 30th Anniversary Edition, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Dan Frazier Card Text:This version of this card has a non-standard Magic back. It is not legal for constructed play.
Swamp (003) - Arena League Promo 1996 (PARL) from Arena League 1996, available at 401 Games Canada. Rarity: Rare Finish: Normal Artist: Tony Roberts Card Text:T: Add B to your mana pool.
Swamp (346) (Foil) (7ED) from Seventh Edition, available at 401 Games Canada. Rarity: Common Finish: Foil Artist: D. J. Cleland-Hura
Swamp (1952) - Marvel's Spider-Man: Mana Symbiote (Raised Foil) (SLD) from Secret Lair Drop, available at 401 Games Canada. Rarity: Rare Finish: Foil Artist: Pedro Potier Card Text: Marvel's Spider-Man: Mana Symbiote
Swamp (296) (LEB) from Limited Edition Beta, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Dan Frazier Card Text:Tap to add B to your mana pool.
Swamp (061) (DDC) from Duel Decks: Divine vs. Demonic, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: John Avon
Swamp (066) (DDR) from Duel Decks: Nissa vs. Ob Nixilis, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Noah Bradley
Swamp (062) (DDC) from Duel Decks: Divine vs. Demonic, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Vance Kovacs
Swamp (061) (ITP) from Introductory Two-Player Set, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Dan Frazier Card Text:T: Add B to your mana pool.The version of this card features a Copyright date of © 1996.
Swamp (376) (CST) from Coldsnap Theme Decks, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Douglas Shuler
Swamp (384) - The Astrology Lands (SLD) from Secret Lair Drop, available at 401 Games Canada. Rarity: Rare Finish: Normal Artist: Jeanne D'Angelo Card Text: Zodiac Lands(T: Add B.)
Swamp (069) (DDR) from Duel Decks: Nissa vs. Ob Nixilis, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Jung Park
Swamp (060) (ITP) from Introductory Two-Player Set, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Dan Frazier Card Text:T: Add B to your mana pool.The version of this card features a Copyright date of © 1996.
Swamp (010) (PALP) from Asia Pacific Land Program, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Ron Spears Card Text:T: Add B to your mana pool.
Swamp (015) (PELP) from European Land Program, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Mike Ploog
Swamp (009) - Arena League Promo 1999 (Foil) (PAL99) from Arena League 1999, available at 401 Games Canada. Rarity: Rare Finish: Foil Artist: John Avon Card Text:T: Add B to your mana pool.
Swamp (291) (LEA) from Limited Edition Alpha, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Dan Frazier
Swamp - Art Series (Gold-Stamped Signature) (AFDN) from Foundations Art Series, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Steven Belledin
Swamp (005) (PELP) from European Land Program, available at 401 Games Canada. Rarity: Common Finish: Normal Artist: Scott Bailey
Swamp (1470) - Pixel Lands 02.jpg (Foil) (SLD) from Secret Lair Drop, available at 401 Games Canada. Rarity: Rare Finish: Foil Artist: Jubilee Card Text: Pixel Lands 02.jpg
Swamp (033) (SLP) from Secret Lair Promo, available at 401 Games Canada. Rarity: Rare Finish: Normal Artist: John Avon
Swamp (417) - Shades Not Included (Foil) (SLD) from Secret Lair Drop, available at 401 Games Canada. Rarity: Rare Finish: Foil Artist: Ben Schnuck Card Text: Shades Not Included
Swamp (033) (Foil) (SLP) from Secret Lair Promo, available at 401 Games Canada. Rarity: Rare Finish: Foil Artist: John Avon
Swamp (048) - The Tokyo Lands - Japanese (SLD) from Secret Lair Drop, available at 401 Games Canada. Rarity: Rare Finish: Normal Artist: Mr. Misang Card Text: The Tokyo Lands