Mystery Booster 2

Creature — Wraith

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Cycling—Pay 2 life. (Pay 2 life, Discard this card: Draw a card.)

Street Wraith

Ravnica Remastered

Creature — Zombie

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Scavenge {2}{B} ({2}{B}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Sewer Shambler

Multiverse Legends

Legendary Creature — Phyrexian Praetor

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature of their choice.

Sheoldred, Whispering One

Unknown Event

Legendary Creature — Cat Gamer

Islandwalk, swampwalk (This creature can't be blocked if defending player controls an Island or a Swamp)
Whenever The Milling Runner deals combat damage to a player, target player mills three cards.
Ready to run (You can have two commanders if both have ready to run.)

The Milling Runner

Dominaria Remastered

Legendary Creature — Demon

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Whenever a player casts a black spell, you gain 1 life.

Sol'kanar the Swamp King

30th Anniversary Edition

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Bog Wraith

New Capenna Commander

Legendary Creature — Kraken

Islandwalk, swampwalk (This creature can't be blocked as long as defending player controls an Island or a Swamp.)
Whenever Wrexial deals combat damage to a player, you may cast target instant or sorcery card from that player's graveyard without paying its mana cost. If that spell would be put into a graveyard, exile it instead.

Wrexial, the Risen Deep

Time Spiral Remastered

Creature — Snake

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{G}: Regenerate this creature. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Mire Boa

The List

Creature — Phyrexian Horror

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
When this creature dies, each opponent loses 2 life.

Blistergrub

Creature — Incarnation

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
As long as this card is in your graveyard and you control a Swamp, creatures you control have swampwalk.

Filth

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{B}: This creature gets +1/+0 until end of turn.

Dirtwater Wraith

Creature — Horror

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{T}: Add {B}{B}{B}{B}. Target opponent gains control of this creature. (Activate only as an instant.)

Witch Engine

Conspiracy

Creature — Vampire Rogue

Multikicker {1}{B} (You may pay an additional {1}{B} any number of times as you cast this spell.)
Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
This creature enters with a +1/+1 counter on it for each time it was kicked.

Quag Vampires

Avacyn Restored

Creature — Human Scout

Farbog Explorer

Salvat 2011

Creature — Insect

Plague Beetle

Magic 2011

Bog Raiders

Worldwake

Creature — Kor Scout

Marsh Threader

Zendikar

Bog Tatters

Eventide

Creature — Hag

Swampwalk, forestwalk (This creature can't be blocked as long as defending player controls a Swamp or a Forest.)

Stalker Hag

Lorwyn

Creature — Treefolk Shaman

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Whenever a player casts a Goblin spell, you may pay {G}. If you do, you gain 2 life.

Bog-Strider Ash

Ravnica: City of Guilds

Creature — Spirit

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Sacrifice this creature: Exile target card from a graveyard.

Sewerdreg

Ninth Edition

Anaconda

Onslaught

Creature — Zombie Frog Beast

Anurid Murkdiver

Torment

Creature — Nightmare Horror

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
When this creature enters, exile target green or white creature an opponent controls.
When this creature leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Slithery Stalker

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{T}: Target black creature gets -2/-0 until end of turn.

Krosan Constrictor

Odyssey

Creature — Shade

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{B}: This creature gets +1/+1 until end of turn.

Whispering Shade

Prophecy

Marsh Boa

Mercadian Masques

Creature — Human Mercenary

Bog Smugglers

Creature — Horror Mercenary

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{5}, {T}: Search your library for a Mercenary permanent card with mana value 5 or less, put it onto the battlefield, then shuffle.

Cateran Slaver

Starter 1999

Creature — Ox

Wild Ox

Portal Three Kingdoms

Creature — Boar

Zodiac Pig

Creature — Rat

Zodiac Rat

Zodiac Snake

Zodiac Ox

Classic Sixth Edition

Creature — Spirit Minion

Lost Soul

Warthog

Portal Second Age

Creature — Nightstalker

Raiding Nightstalker

Tempest

Flying; swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Bayou Dragonfly

Weatherlight

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Whenever this creature deals damage to a player, that player discards a card.