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.

Sol Ring

Grand Abolisher

During your turn, your opponents can't cast spells or activate abilities of artifacts, creatures, or enchantments.

Gigadrowse

Replicate {U} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Tap target permanent.

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.

Alaborn Cavalier

Whenever Alaborn Cavalier attacks, you may tap target creature.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Retreat to Coralhelm

Landfall — Whenever a land you control enters, choose one —
• You may tap or untap target creature.
• Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Knight of the White Orchid

First strike
When Knight of the White Orchid enters, if an opponent controls more lands than you, you may search your library for a Plains card, put it onto the battlefield, then shuffle.

Training Grounds

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Ballynock Trapper

{T}: Tap target creature.
Whenever you cast a white spell, you may untap Ballynock Trapper.

Command Tower

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

Blessed Alliance

Escalate {2} (Pay this cost for each mode chosen beyond the first.)
Choose one or more —
• Target player gains 4 life.
• Untap up to two target creatures.
• Target opponent sacrifices an attacking creature of their choice.

Vitality Hunter

Lifelink
{X}{W}{W}: Monstrosity X. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.)
When Vitality Hunter becomes monstrous, put a lifelink counter on each of up to X target creatures.

Heartstone

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Akroan Jailer

Benalish Trapper

Aerial Assault

Destroy target tapped creature. You gain 1 life for each creature you control with flying.

Banish from Edoras

This spell costs {2} less to cast if it targets a tapped creature.
Exile target creature.

Artillery Blast

Domain — Artillery Blast deals X damage to target tapped creature, where X is 1 plus the number of basic land types among lands you control.

Brightmare

When Brightmare enters, tap up to one target creature. You gain life equal to that creature's power.

Elemental

Akroan Mastiff

Magewright's Stone

{1}, {T}: Untap target creature that has an activated ability with {T} in its cost.

Octopus Umbra

Enchant creature
Enchanted creature has base power and toughness 8/8 and has "Whenever this creature attacks, you may tap target creature with power 8 or less."
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Treasure

{T}, Sacrifice this token: Add one mana of any color.

Aysen Bureaucrats

{T}: Tap target creature with power 2 or less.

Throne of the God-Pharaoh

At the beginning of your end step, each opponent loses life equal to the number of tapped creatures you control.

Blinding Mage

Dizzying Swoop

Tap up to two target creatures. (Then exile this card. You may cast the creature later from exile.)

Ardenvale Tactician

Ardenvale Tactician // Dizzying Swoop

Avacynian Priest

Aetherstorm Roc

Flying
Whenever Aetherstorm Roc or another creature you control enters, you get {E} (an energy counter).
Whenever Aetherstorm Roc attacks, you may pay {E}{E}. If you do, put a +1/+1 counter on it and tap up to one target creature defending player controls.

Beacon Hawk

Flying
Whenever Beacon Hawk deals combat damage to a player, you may untap target creature.
{W}: Beacon Hawk gets +0/+1 until end of turn.

Angelic Benediction

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever a creature you control attacks alone, you may tap target creature.

Blinding Beam

Choose one —
• Tap two target creatures.
• Creatures don't untap during target player's next untap step.
Entwine {1} (Choose both if you pay the entwine cost.)

Grand Arbiter Augustin IV

White spells you cast cost {1} less to cast.
Blue spells you cast cost {1} less to cast.
Spells your opponents cast cost {1} more to cast.

Agatha's Soul Cauldron

You may spend mana as though it were mana of any color to activate abilities of creatures you control.
Creatures you control with +1/+1 counters on them have all activated abilities of all creature cards exiled with Agatha's Soul Cauldron.
{T}: Exile target card from a graveyard. When a creature card is exiled this way, put a +1/+1 counter on target creature you control.