Hylda of the Icy Crown

Whenever you tap an untapped creature an opponent controls, you may pay {1}. When you do, choose one —
• Create a 4/4 white and blue Elemental creature token.
• Put a +1/+1 counter on each creature you control.
• Scry 2, then draw a card.

Timin, Youthful Geist

Partner with Rhoda, Geist Avenger (When this creature enters, target player may put Rhoda into their hand from their library, then shuffle.)
Flying
At the beginning of each combat, tap up to one target creature.

Snow-Covered Plains

Hammers of Moradin

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Whenever this creature attacks, for each opponent, tap up to one target creature that player controls.

Teferi, Who Slows the Sunset

+1: Choose up to one target artifact, up to one target creature, and up to one target land. Untap the chosen permanents you control. Tap the chosen permanents you don't control. You gain 2 life.
−2: Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.
−7: You get an emblem with "Untap all permanents you control during each opponent's untap step" and "You draw a card during each opponent's draw step."

Tamiyo, the Moon Sage

+1: Tap target permanent. It doesn't untap during its controller's next untap step.
−2: Draw a card for each tapped creature target player controls.
−8: You get an emblem with "You have no maximum hand size" and "Whenever a card is put into your graveyard from anywhere, you may return it to your hand."

Blustersquall

Tap target creature you don't control.
Overload {3}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Theft of Dreams

Draw a card for each tapped creature target opponent controls.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. This land deals 1 damage to you.

Hylda's Crown of Winter

{1}, {T}: Tap target creature. This ability costs {1} less to activate during your turn.
{3}, Sacrifice Hylda's Crown of Winter: Draw a card for each tapped creature your opponents control.

Willbreaker

Whenever a creature an opponent controls becomes the target of a spell or ability you control, gain control of that creature for as long as you control this creature.

Frost Titan

Whenever this creature becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {2}.
Whenever this creature enters or attacks, tap target permanent. It doesn't untap during its controller's next untap step.

Frostwalk Bastion

{T}: Add {C}.
{1}{S}: Until end of turn, this land becomes a 2/3 Construct artifact creature. It's still a land. ({S} can be paid with one mana from a snow source.)
Whenever this land deals combat damage to a creature, tap that creature and it doesn't untap during its controller's next untap step.

Fear of Sleep Paralysis

Flying
Eerie — Whenever this creature or another enchantment you control enters and whenever you fully unlock a Room, tap up to one target creature and put a stun counter on it.
Stun counters can't be removed from permanents your opponents control. (They won't untap if they have stun counters.)

Mjölnir, Storm Hammer

When Mjölnir enters, attach it to target legendary creature you control.
Whenever equipped creature attacks, tap target creature defending player controls and put a stun counter on it. Then Mjölnir deals damage to each opponent equal to the number of tapped creatures that opponent controls.
Equip {4}

Assassin Gauntlet

When this Equipment enters, attach it to up to one target creature you control. Tap all creatures target opponent controls.
Equipped creature gets +1/+1 and has "Whenever this creature deals combat damage to a player, draw a card, then discard a card."
Equip {2}

Arcane Lighthouse

{T}: Add {C}.
{1}, {T}: Until end of turn, creatures your opponents control lose hexproof and shroud and can't have hexproof or shroud.

Split Up

Choose one —
• Destroy all tapped creatures.
• Destroy all untapped creatures.

Talisman of Progress

{T}: Add {C}.
{T}: Add {W} or {U}. This artifact deals 1 damage to you.

Glacial Fortress

This land enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Snow-Covered Island

Righteous Fury

Destroy all tapped creatures. You gain 2 life for each creature destroyed this way.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Scroll of Isildur

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Gain control of up to one target artifact for as long as you control this Saga. The Ring tempts you.
II — Tap up to two target creatures. Put a stun counter on each of them.
III — Draw a card for each tapped creature target opponent controls.

Court Street Denizen

Whenever another white creature you control enters, tap target creature an opponent controls.

Plant Tadpoles

Tap X target creatures. They don't untap during their controllers' next untap steps. (Then exile this card. You may cast the creature later from exile.)

Illithid Harvester

Ceremorphosis — When this creature enters, turn any number of target tapped nontoken creatures face down. They're 2/2 Horror creatures.

Illithid Harvester // Plant Tadpoles

Citadel Siege

As this enchantment enters, choose Khans or Dragons.
• Khans — At the beginning of combat on your turn, put two +1/+1 counters on target creature you control.
• Dragons — At the beginning of combat on each opponent's turn, tap target creature that player controls.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Succumb to the Cold

Tap one or two target creatures an opponent controls. Put a stun counter on each of them. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Prairie Stream

({T}: Add {W} or {U}.)
This land enters tapped unless you control two or more basic lands.

Elvish Mariner

Whenever this creature attacks, scry 1.
Whenever you scry, tap up to X target nonland permanents, where X is the number of cards looked at while scrying this way.

Stroke of Midnight

Destroy target nonland permanent. Its controller creates a 1/1 white Human creature token.

Gideon's Lawkeeper

Dreamshackle Geist

Flying
At the beginning of combat on your turn, choose up to one —
• Tap target creature.
• Target creature doesn't untap during its controller's next untap step.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Exotic Orchard

Sharae of Numbing Depths

When Sharae enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you tap one or more untapped creatures your opponents control, draw a card. This ability triggers only once each turn.

Feeling of Dread

Tap up to two target creatures.
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Gideon's Avenger

Whenever a creature an opponent controls becomes tapped, put a +1/+1 counter on this creature.

Icy Blast

Tap X target creatures.
Ferocious — If you control a creature with power 4 or greater, those creatures don't untap during their controllers' next untap steps.

Arcane Signet

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

Plunge into Winter

Tap up to one target creature. Scry 1, then draw a card.

Bond of Discipline

Tap all creatures your opponents control. Creatures you control gain lifelink until end of turn.

Opposition

Tap an untapped creature you control: Tap target artifact, creature, or land.

Time of Ice

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Tap target creature an opponent controls. It doesn't untap during its controller's untap step for as long as you control this Saga.
III — Return all tapped creatures to their owners' hands.

Minister of Impediments

({W/U} can be paid with either {W} or {U}.)
{T}: Tap target creature.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Cone of Cold

Roll a d20.
1—9 | Tap all creatures your opponents control.
10—19 | Tap all creatures your opponents control. Those creatures don't untap during their controllers' next untap steps.
20 | Tap all creatures your opponents control. Those creatures don't untap during their controllers' next untap steps. Until your next turn, creatures your opponents control enter tapped.

Detection Tower

{T}: Add {C}.
{1}, {T}: Until end of turn, your opponents and creatures your opponents control with hexproof can be the targets of spells and abilities you control as though they didn't have hexproof.

Junk Winder

Affinity for tokens (This spell costs {1} less to cast for each token you control.)
Whenever a token you control enters, tap target nonland permanent an opponent controls. It doesn't untap during its controller's next untap step.

Chop Down

Destroy target creature with power 4 or greater. (Then exile this card. You may cast the creature later from exile.)

Giant Killer

Giant Killer // Chop Down

Sunblast Angel

Flying
When this creature enters, destroy all tapped creatures.

Rhoda, Geist Avenger

Partner with Timin, Youthful Geist (When this creature enters, target player may put Timin into their hand from their library, then shuffle.)
Vigilance
Whenever a creature an opponent controls becomes tapped, if it isn't being declared as an attacker, put a +1/+1 counter on Rhoda.

Orderly Plaza

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

Suppression Ray

Tap all creatures target player controls. You may pay any amount of {E}. If you do, choose up to that many creatures tapped this way. Put a stun counter on each of them. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Suppression Ray // Orderly Plaza

Freeze in Place

Tap target creature an opponent controls and put three stun counters on it. Scry 2. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Topplegeist

Flying
When this creature enters, tap target creature an opponent controls.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, tap target creature that player controls.

Mystic Gate

{T}: Add {C}.
{W/U}, {T}: Add {W}{W}, {W}{U}, or {U}{U}.

Sol Ring

Githzerai Monk

Flash
Flying
Psychic Defense — When this creature enters, tap all creatures you don't control.

Icewrought Sentry

Vigilance
Whenever this creature attacks, you may pay {1}{U}. When you do, tap target creature an opponent controls.
Whenever you tap an untapped creature an opponent controls, this creature gets +2/+1 until end of turn.

Sleep

Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.

Gadwick, the Wizened

When Gadwick enters, draw X cards.
Whenever you cast a blue spell, tap target nonland permanent an opponent controls.

Azorius Signet

Downpour

Solitary Sanctuary

When this enchantment enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you tap an untapped creature an opponent controls, put a +1/+1 counter on target creature you control.

Lost in the Maze

Flash
When this enchantment enters, tap X target creatures. Put a stun counter on each of those creatures you don't control. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Tapped creatures you control have hexproof.

Deserted Beach

This land enters tapped unless you control two or more other lands.
{T}: Add {W} or {U}.

Command Tower

Cryptic Command

Choose two —
• Counter target spell.
• Return target permanent to its owner's hand.
• Tap all creatures your opponents control.
• Draw a card.

Soporific Springs

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {U}.

Sink into Stupor

Return target spell or nonland permanent an opponent controls to its owner's hand.

Sink into Stupor // Soporific Springs

Verity Circle

Whenever a creature an opponent controls becomes tapped, if it isn't being declared as an attacker, you may draw a card.
{4}{U}: Tap target creature without flying.

Borrowing 100,000 Arrows

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Counterspell

Don't Move

Destroy all tapped creatures. Until your next turn, whenever a creature becomes tapped, destroy it.