Library of Leng

You have no maximum hand size.
If an effect causes you to discard a card, discard it, but you may put it on top of your library instead of into your graveyard.

Cunning Lethemancer

At the beginning of your upkeep, each player discards a card.

Medicine Bag

{1}, {T}, Discard a card: Regenerate target creature.

Mind Over Matter

Discard a card: You may tap or untap target artifact, creature, or land.

Swamp

Trickster Mage

{U}, {T}, Discard a card: You may tap or untap target artifact, creature, or land.

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Circuitous Route

Search your library for up to two basic land cards and/or Gate cards, put them onto the battlefield tapped, then shuffle.

Nostalgic Dreams

As an additional cost to cast this spell, discard X cards.
Return X target cards from your graveyard to your hand. Exile Nostalgic Dreams.

Skirge Familiar

Walk the Plank

Silverglade Pathfinder

{1}{G}, {T}, Discard a card: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Haunted Dead

When Haunted Dead enters, create a 1/1 white Spirit creature token with flying.
{1}{B}, Discard two cards: Return Haunted Dead from your graveyard to the battlefield tapped.

Darkwater Catacombs

Sol Ring

Grimoire of the Dead

{1}, {T}, Discard a card: Put a study counter on Grimoire of the Dead.
{T}, Remove three study counters from Grimoire of the Dead and sacrifice it: Put all creature cards from all graveyards onto the battlefield under your control. They're black Zombies in addition to their other colors and types.

Explosive Vegetation

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Awaken the Erstwhile

Each player discards all the cards in their hand, then creates that many 2/2 black Zombie creature tokens.

Manabond

At the beginning of your end step, you may reveal your hand and put all land cards from it onto the battlefield. If you do, discard your hand.

Damia, Sage of Stone

Deathtouch
Skip your draw step.
At the beginning of your upkeep, if you have fewer than seven cards in hand, draw cards equal to the difference.

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters tapped unless you control two or more basic lands.

Big Game Hunter

When Big Game Hunter enters, destroy target creature with power 4 or greater. It can't be regenerated.
Madness {B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Mindslicer

When Mindslicer dies, each player discards their hand.

Morphic Pool

Morphic Pool enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Breeding Pool

({T}: Add {G} or {U}.)
As Breeding Pool enters, you may pay 2 life. If you don't, it enters tapped.

Bottomless Pit

At the beginning of each player's upkeep, that player discards a card at random.

Creeping Dread

At the beginning of your upkeep, each player discards a card. Each opponent who discarded a card that shares a card type with the card you discarded loses 3 life. (Players reveal the discarded cards simultaneously.)

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Forbid

Buyback—Discard two cards. (You may discard two cards in addition to any other costs as you cast this spell. If you do, put this card into your hand as it resolves.)
Counter target spell.

Turbulent Dreams

As an additional cost to cast this spell, discard X cards.
Return X target nonland permanents to their owners' hands.

Choked Estuary

As Choked Estuary enters, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters tapped.
{T}: Add {U} or {B}.

Rites of Refusal

Discard any number of cards. Counter target spell unless its controller pays {3} for each card discarded this way.

Misty Rainforest

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

Archfiend of Ifnir

Flying
Whenever you cycle or discard another card, put a -1/-1 counter on each creature your opponents control.
Cycling {2} ({2}, Discard this card: Draw a card.)

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Greenseeker

{G}, {T}, Discard a card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Descent into Madness

At the beginning of your upkeep, put a despair counter on Descent into Madness, then each player exiles X permanents they control and/or cards from their hand, where X is the number of despair counters on Descent into Madness.

Forest

Defense of the Heart

At the beginning of your upkeep, if an opponent controls three or more creatures, sacrifice Defense of the Heart, search your library for up to two creature cards, put those cards onto the battlefield, then shuffle.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Painful Quandary

Whenever an opponent casts a spell, that player loses 5 life unless they discard a card.

Island

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Snag

You may discard a Forest card rather than pay this spell's mana cost.
Prevent all combat damage that would be dealt by unblocked creatures this turn.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Diplomatic Escort

{U}, {T}, Discard a card: Counter target spell or ability that targets a creature.

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Bog Witch

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Overgrown Tomb

({T}: Add {B} or {G}.)
As Overgrown Tomb enters, you may pay 2 life. If you don't, it enters tapped.

Murderous Cut

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Destroy target creature.

Overtaker

{3}{U}, {T}, Discard a card: Untap target creature and gain control of it until end of turn. That creature gains haste until end of turn.

Gorgon Recluse

Whenever Gorgon Recluse blocks or becomes blocked by a nonblack creature, destroy that creature at end of combat.
Madness {B}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Opulent Palace

Opulent Palace enters tapped.
{T}: Add {B}, {G}, or {U}.

Terrain Generator

{T}: Add {C}.
{2}, {T}: You may put a basic land card from your hand onto the battlefield tapped.

Seedborn Muse

Untap all permanents you control during each other player's untap step.

Null Brooch

{2}, {T}, Discard your hand: Counter target noncreature spell.

Stronghold Biologist

{U}{U}, {T}, Discard a card: Counter target creature spell.

Watery Grave

({T}: Add {U} or {B}.)
As Watery Grave enters, you may pay 2 life. If you don't, it enters tapped.

Tragic Slip

Target creature gets -1/-1 until end of turn.
Morbid — That creature gets -13/-13 until end of turn instead if a creature died this turn.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Praetor's Counsel

Return all cards from your graveyard to your hand. Exile Praetor's Counsel. You have no maximum hand size for the rest of the game.

Necrogen Mists

At the beginning of each player's upkeep, that player discards a card.

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. Underground River deals 1 damage to you.

Instigator

{1}{B}{B}, {T}, Discard a card: Creatures target player controls attack this turn if able.

Dawnstrider

{G}, {T}, Discard a card: Prevent all combat damage that would be dealt this turn.

Genesis

At the beginning of your upkeep, if Genesis is in your graveyard, you may pay {2}{G}. If you do, return target creature card from your graveyard to your hand.

Kodama's Reach

Circular Logic

Counter target spell unless its controller pays {1} for each card in your graveyard.
Madness {U} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Putrefy

Destroy target artifact or creature. It can't be regenerated.

Stronghold Machinist

{U}{U}, {T}, Discard a card: Counter target noncreature spell.

Alhammarret's Archive

If you would gain life, you gain twice that much life instead.
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Darksteel Plate

Indestructible
Equipped creature has indestructible.
Equip {2}

Skyshroud Claim

Search your library for up to two Forest cards, put them onto the battlefield, then shuffle.

Hinterland Harbor

Hinterland Harbor enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Rites of Spring

Discard any number of cards. Search your library for up to that many basic land cards, reveal them, put them into your hand, then shuffle.

Woodland Cemetery

Woodland Cemetery enters tapped unless you control a Swamp or a Forest.
{T}: Add {B} or {G}.

Memory

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Each player shuffles their hand and graveyard into their library, then draws seven cards.

Commit

Put target spell or nonland permanent into its owner's library second from the top.

Commit // Memory

Sultai Charm

Choose one —
• Destroy target monocolored creature.
• Destroy target artifact or enchantment.
• Draw two cards, then discard a card.

Llanowar Wastes

{T}: Add {C}.
{T}: Add {B} or {G}. Llanowar Wastes deals 1 damage to you.

Alexi, Zephyr Mage

{X}{U}, {T}, Discard two cards: Return X target creatures to their owners' hands.

Waterfront Bouncer

{U}, {T}, Discard a card: Return target creature to its owner's hand.

Dream Halls

Rather than pay the mana cost for a spell, its controller may discard a card that shares a color with that spell.