Elrond, Lord of Rivendell

Whenever Elrond, Lord of Rivendell or another creature you control enters, scry 1. If this is the second time this ability has resolved this turn, the Ring tempts you.

Kotose, the Silent Spider

When Kotose, the Silent Spider enters, exile target card other than a basic land card from an opponent's graveyard. Search that player's graveyard, hand, and library for any number of cards with the same name as that card and exile them. Then that player shuffles. For as long as you control Kotose, you may play one of the exiled cards, and you may spend mana as though it were mana of any color to cast it.

Nettling Imp

{T}: Choose target non-Wall creature the active player has controlled continuously since the beginning of the turn. That creature attacks this turn if able. Destroy it at the beginning of the next end step if it didn't attack this turn. Activate only during an opponent's turn, before attackers are declared.

Oath of Scholars

At the beginning of each player's upkeep, that player chooses target player who has more cards in hand than they do and is their opponent. The first player may discard their hand and draw three cards.

Vampire Hounds

Discard a creature card: Vampire Hounds gets +2/+2 until end of turn.

Frozen Shade

{B}: Frozen Shade gets +1/+1 until end of turn.

Pestilence

At the beginning of the end step, if no creatures are on the battlefield, sacrifice Pestilence.
{B}: Pestilence deals 1 damage to each creature and each player.

Rictus Robber

When Rictus Robber enters, if a creature died this turn, create a 2/2 blue and black Zombie Rogue creature token.
Plot {2}{B} (You may pay {2}{B} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Drafna's Restoration

Put any number of target artifact cards from target player's graveyard on top of their library in any order.

Helm of Chatzuk

{1}, {T}: Target creature gains banding until end of turn. (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding a player controls are blocking or being blocked by a creature, that player divides that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

Necrologia

Cast this spell only during your end step.
As an additional cost to cast this spell, pay X life.
Draw X cards.

Rootwater Hunter

{T}: Rootwater Hunter deals 1 damage to any target.

Devouring Deep

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Dark Ritual

Evincar's Justice

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Evincar's Justice deals 2 damage to each creature and each player.

Drain Life

Spend only black mana on X.
Drain Life deals X damage to any target. You gain life equal to the damage dealt, but not more life than the player's life total before the damage was dealt, the planeswalker's loyalty before the damage was dealt, or the creature's toughness.

Vesuvan Doppelganger

You may have Vesuvan Doppelganger enter as a copy of any creature on the battlefield, except it doesn't copy that creature's color and it has "At the beginning of your upkeep, you may have this creature become a copy of target creature, except it doesn't copy that creature's color and it has this ability."

Meldweb Strider

Vigilance
Meldweb Strider enters with an oil counter on it.
Remove an oil counter from Meldweb Strider: It becomes an artifact creature until end of turn.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Weakness

Enchant creature
Enchanted creature gets -2/-1.

Deceive the Messenger

Target creature gets -3/-0 until end of turn.
Amass Orcs 1. (Put a +1/+1 counter on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)

Urza's Tower

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

Brass Man

Brass Man doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {1}. If you do, untap Brass Man.

Sam's Desperate Rescue

Return target creature card from your graveyard to your hand. The Ring tempts you.

Mana Leak

Counter target spell unless its controller pays {3}.

Desert's Due

Target creature gets -2/-2 until end of turn. It gets an additional -1/-1 until end of turn for each Desert you control.

Nausea

All creatures get -1/-1 until end of turn.

Swamp

Howl from Beyond

Target creature gets +X/+0 until end of turn.

Capsize

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Return target permanent to its owner's hand.

Treasure Trove

High-Speed Hoverbike

Flash
Flying
When High-Speed Hoverbike enters, tap up to one target creature.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Quicksilver Fisher

Flying
When Quicksilver Fisher enters, draw a card, then discard a card.

Clone

You may have Clone enter as a copy of any creature on the battlefield.

Dauthi Jackal

Shadow (This creature can block or be blocked by only creatures with shadow.)
{B}{B}, Sacrifice Dauthi Jackal: Destroy target blocking creature.

Dark Banishing

Destroy target nonblack creature. It can't be regenerated.

Water Elemental

Island

The Rack

As The Rack enters, choose an opponent.
At the beginning of the chosen player's upkeep, The Rack deals X damage to that player, where X is 3 minus the number of cards in their hand.

Raise Dead

Return target creature card from your graveyard to your hand.

Merfolk of the Pearl Trident

Spell Blast

Counter target spell with mana value X. (For example, if that spell's mana cost is {3}{U}{U}, X is 5.)

Treason of Isengard

Put up to one target instant or sorcery card from your graveyard on top of your library.
Amass Orcs 2. (To amass Orcs 2, put two +1/+1 counters on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)

Blue Elemental Blast

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

Bewitching Leechcraft

Enchant creature
When Bewitching Leechcraft enters, tap enchanted creature.
Enchanted creature has "If this creature would untap during your untap step, remove a +1/+1 counter from it instead. If you do, untap it." (Otherwise, it doesn't untap.)

Manta Riders

{U}: Manta Riders gains flying until end of turn.

Reality Heist

This spell costs {1} less to cast for each artifact you control.
Look at the top seven cards of your library. You may reveal up to two artifact cards from among them and put them into your hand. Put the rest on the bottom of your library in a random order.

Throne of Bone

Whenever a player casts a black spell, you may pay {1}. If you do, you gain 1 life.

Gloom

White spells cost {3} more to cast.
Activated abilities of white enchantments cost {3} more to activate.

Stop Cold

Flash
Enchant artifact or creature
When Stop Cold enters, tap enchanted permanent.
Enchanted permanent loses all abilities and doesn't untap during its controller's untap step.

Animate Artifact

Enchant artifact
As long as enchanted artifact isn't a creature, it's an artifact creature with power and toughness each equal to its mana value.

Darkslick Shores

Darkslick Shores enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

Flight

Enchant creature
Enchanted creature has flying.

Lord of Atlantis

Other Merfolk get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)

Scavenging Ghoul

At the beginning of each end step, put a corpse counter on Scavenging Ghoul for each creature that died this turn.
Remove a corpse counter from Scavenging Ghoul: Regenerate Scavenging Ghoul.

Sacrifice

As an additional cost to cast this spell, sacrifice a creature.
Add an amount of {B} equal to the sacrificed creature's mana value.

Terror

Destroy target nonartifact, nonblack creature. It can't be regenerated.

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.

Merfolk Looter

Creature Bond

Enchant creature
When enchanted creature dies, Creature Bond deals damage equal to that creature's toughness to the creature's controller.

Phantasmal Forces

Flying
At the beginning of your upkeep, sacrifice Phantasmal Forces unless you pay {U}.

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Force Spike

Counter target spell unless its controller pays {1}.

Lembas

When Lembas enters, scry 1, then draw a card.
{2}, {T}, Sacrifice Lembas: You gain 3 life.
When Lembas is put into a graveyard from the battlefield, its owner shuffles it into their library.

Sengir Vampire

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever a creature dealt damage by Sengir Vampire this turn dies, put a +1/+1 counter on Sengir Vampire.

Thrull Surgeon

{1}{B}, Sacrifice Thrull Surgeon: Look at target player's hand and choose a card from it. That player discards that card. Activate only as a sorcery.

Psychic Venom

Enchant land
Whenever enchanted land becomes tapped, Psychic Venom deals 2 damage to that land's controller.

Keeper of the Mind

{U}, {T}: Choose target opponent who has at least two more cards in hand than you do as you activate this ability. Draw a card.