Have

Swamp

Cadaver Lab

When you unlock this door, return target creature card from your graveyard to your hand.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Defiled Crypt

Whenever one or more cards leave your graveyard, create a 2/2 black Horror enchantment creature token. This ability triggers only once each turn.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Defiled Crypt // Cadaver Lab

Contaminated Aquifer

({T}: Add {U} or {B}.)
This land enters tapped.

Erase

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Tainted Strike

Target creature gets +1/+0 and gains infect until end of turn. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Blacksmith's Skill

Target permanent gains hexproof and indestructible until end of turn. If it's an artifact creature, it gets +2/+2 until end of turn.

Blue Elemental Blast

Choose one —
• Counter target red spell.
• Destroy target red permanent.

Helping Hand

Return target creature card with mana value 3 or less from your graveyard to the battlefield tapped.

Street 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.)

Horseshoe Crab

Sunlit Marsh

({T}: Add {W} or {B}.)
This land enters tapped.

Hard Evidence

Create a 0/3 blue Crab creature token.
Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Gravedig

Choose one —
• Target player creates a 2/2 black Zombie creature token.
• Return target creature card from your graveyard to your hand.
Entwine {2} (Choose both if you pay the entwine cost.)

Spirit Link

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Whenever enchanted creature deals damage, you gain that much life.

Plains

Island

Phyresis

Enchant creature
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Unearth

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Hermetic Study

Enchant creature
Enchanted creature has "{T}: This creature deals 1 damage to any target."

Negate

Counterspell

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Toxin Analysis

Target creature gains deathtouch and lifelink until end of turn. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Disenchant

Idyllic Beachfront

({T}: Add {W} or {U}.)
This land enters tapped.

Contaminated Landscape

{T}: Add {C}.
{T}, Sacrifice this land: Search your library for a basic Plains, Island, or Swamp card, put it onto the battlefield tapped, then shuffle.
Cycling {W}{U}{B} ({W}{U}{B}, Discard this card: Draw a card.)

Echoing Return

Return target creature card and all other cards with the same name as that card from your graveyard to your hand.