Veteran of the Depths

Whenever Veteran of the Depths becomes tapped, you may put a +1/+1 counter on it.

Satyr Nyx-Smith

Haste
Inspired — Whenever Satyr Nyx-Smith becomes untapped, you may pay {2}{R}. If you do, create a 3/1 red Elemental enchantment creature token with haste.

Castle

Untapped creatures you control get +0/+2.

Oreskos Sun Guide

Inspired — Whenever Oreskos Sun Guide becomes untapped, you gain 2 life.

Palladium Myr

Smoke

Players can't untap more than one creature during their untap steps.

Gideon, Martial Paragon

+2: Untap all creatures you control. Those creatures get +1/+1 until end of turn.
0: Until end of turn, Gideon, Martial Paragon becomes a 5/5 Human Soldier creature with indestructible that's still a planeswalker. Prevent all damage that would be dealt to him this turn.
−10: Creatures you control get +2/+2 until end of turn. Tap all creatures your opponents control.

Battlemage's Bracers

Equipped creature has haste.
Whenever an ability of equipped creature is activated, if it isn't a mana ability, you may pay {1}. If you do, copy that ability. You may choose new targets for the copy.
Equip {2}

Juntu Stakes

Creatures with power 1 or less don't untap during their controllers' untap steps.

Sol Ring

Aggravated Assault

{3}{R}{R}: Untap all creatures you control. After this main phase, there is an additional combat phase followed by an additional main phase. Activate only as a sorcery.

Explosive Singularity

As an additional cost to cast this spell, you may tap any number of untapped creatures you control. This spell costs {1} less to cast for each creature tapped this way.
Explosive Singularity deals 10 damage to any target.

Maze of Ith

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.

Dockside Extortionist

When Dockside Extortionist enters, create X Treasure tokens, where X is the number of artifacts and enchantments your opponents control. (Treasure tokens are artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Builder's Blessing

Judge of Currents

Whenever a Merfolk you control becomes tapped, you may gain 1 life.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Samite Alchemist

{W}{W}, {T}: Prevent the next 4 damage that would be dealt this turn to target creature you control. Tap that creature. It doesn't untap during your next untap step.

Sword of the Paruns

As long as equipped creature is tapped, tapped creatures you control get +2/+0.
As long as equipped creature is untapped, untapped creatures you control get +0/+2.
{3}: You may tap or untap equipped creature.
Equip {3}

Masako the Humorless

Flash
Tapped creatures you control can block as though they were untapped.

Puppet Strings

{2}, {T}: You may tap or untap target creature.

Vulshok Gauntlets

Equipped creature gets +4/+2 and doesn't untap during its controller's untap step.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Waves of Aggression

Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Smuggler's Share

At the beginning of each end step, draw a card for each opponent who drew two or more cards this turn, then create a Treasure token for each opponent who had two or more lands enter the battlefield under their control this turn.

Illusionist's Bracers

Whenever an ability of equipped creature is activated, if it isn't a mana ability, copy that ability. You may choose new targets for the copy.
Equip {3}

Stitcher's Graft

Equipped creature gets +3/+3.
Whenever equipped creature attacks, it doesn't untap during its controller's next untap step.
Whenever Stitcher's Graft becomes unattached from a permanent, sacrifice that permanent.
Equip {2}

Prosperous Partnership

When Prosperous Partnership enters, create two 1/1 green and white Citizen creature tokens.
Tap three untapped creatures you control: Create a Treasure token.

Arena of the Ancients

Legendary creatures don't untap during their controllers' untap steps.
When Arena of the Ancients enters, tap all legendary creatures.

Altar Golem

Trample
Altar Golem's power and toughness are each equal to the number of creatures on the battlefield.
Altar Golem doesn't untap during your untap step.
Tap five untapped creatures you control: Untap Altar Golem.

Arcane Signet

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

Hair-Strung Koto

Tap an untapped creature you control: Target player mills a card.

Flawless Maneuver

If you control a commander, you may cast this spell without paying its mana cost.
Creatures you control gain indestructible until end of turn.

Crackdown

Nonwhite creatures with power 3 or greater don't untap during their controllers' untap steps.

Sunstrike Legionnaire

Sunstrike Legionnaire doesn't untap during your untap step.
Whenever another creature enters, untap Sunstrike Legionnaire.
{T}: Tap target creature with mana value 3 or less.

Pristine Angel

Flying
As long as Pristine Angel is untapped, it has protection from artifacts and from each color.
Whenever you cast a spell, you may untap Pristine Angel.

Meekstone

Creatures with power 3 or greater don't untap during their controllers' untap steps.

Archangel of Tithes

Flying
As long as Archangel of Tithes is untapped, creatures can't attack you or planeswalkers you control unless their controller pays {1} for each of those creatures.
As long as Archangel of Tithes is attacking, creatures can't block unless their controller pays {1} for each of those creatures.

Famished Paladin

Famished Paladin doesn't untap during your untap step.
Whenever you gain life, untap Famished Paladin.

Veteran's Voice

Enchant creature you control
Tap enchanted creature: Target creature other than the creature tapped this way gets +2/+1 until end of turn. Activate only if enchanted creature is untapped.

Reconnaissance

{0}: Remove target attacking creature you control from combat and untap it. (If you activate during end of combat, the creature will untap after it deals combat damage.)

Traxos, Scourge of Kroog

Trample
Traxos, Scourge of Kroog enters tapped and doesn't untap during your untap step.
Whenever you cast a historic spell, untap Traxos. (Artifacts, legendaries, and Sagas are historic.)

Relentless Assault

Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.

Augusta, Dean of Order

Other tapped creatures you control get +1/+0.
Other untapped creatures you control get +0/+1.
Whenever you attack, untap each creature you control, then tap any number of creatures you control.

Plargg, Dean of Chaos

{T}, Discard a card: Draw a card.
{4}{R}, {T}: Reveal cards from the top of your library until you reveal a nonlegendary, nonland card with mana value 3 or less. You may cast that card without paying its mana cost. Put all revealed cards not cast this way on the bottom of your library in a random order.

Plargg, Dean of Chaos // Augusta, Dean of Order

Arbalest Elite

{2}{W}, {T}: Arbalest Elite deals 3 damage to target attacking or blocking creature. Arbalest Elite doesn't untap during your next untap step.

Kyren Negotiations

Tap an untapped creature you control: Kyren Negotiations deals 1 damage to target player or planeswalker.

Reveille Squad

Whenever one or more creatures attack you, if Reveille Squad is untapped, you may untap all creatures you control.

Mage-Ring Responder

Mage-Ring Responder doesn't untap during your untap step.
{7}: Untap Mage-Ring Responder.
Whenever Mage-Ring Responder attacks, it deals 7 damage to target creature defending player controls.

Heavy Arbalest

Equipped creature doesn't untap during its controller's untap step.
Equipped creature has "{T}: This creature deals 2 damage to any target."
Equip {4}

Warchanter Skald

Whenever Warchanter Skald becomes tapped, if it's enchanted or equipped, create a 2/1 red Dwarf Berserker creature token.

Aurelia, the Warleader

Flying, vigilance, haste
Whenever Aurelia attacks for the first time each turn, untap all creatures you control. After this phase, there is an additional combat phase.

Kragma Butcher

Inspired — Whenever Kragma Butcher becomes untapped, it gets +2/+0 until end of turn.

God-Favored General

Inspired — Whenever God-Favored General becomes untapped, you may pay {2}{W}. If you do, create two 1/1 white Soldier enchantment creature tokens.

Siege Striker

Double strike (This creature deals both first-strike and regular combat damage.)
Whenever Siege Striker attacks, you may tap any number of untapped creatures you control. Siege Striker gets +1/+1 until end of turn for each creature tapped this way.

Halo Fountain

{W}, {T}, Untap a tapped creature you control: Create a 1/1 green and white Citizen creature token.
{W}{W}, {T}, Untap two tapped creatures you control: Draw a card.
{W}{W}{W}{W}{W}, {T}, Untap fifteen tapped creatures you control: You win the game.

Marble Titan

Lithoform Engine

{2}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
{3}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}, {T}: Copy target permanent spell you control. (The copy becomes a token.)

Iron Myr

Cement Shoes

Equipped creature gets +3/+3 and has "At the beginning of your end step, tap this creature."
Equipped creature doesn't untap during its controller's untap step.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Phyrexian Colossus

Phyrexian Colossus doesn't untap during your untap step.
Pay 8 life: Untap Phyrexian Colossus.
Phyrexian Colossus can't be blocked except by three or more creatures.

Static Orb

As long as Static Orb is untapped, players can't untap more than two permanents during their untap steps.

Colossus of Sardia

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Colossus of Sardia doesn't untap during your untap step.
{9}: Untap Colossus of Sardia. Activate only during your upkeep.

Plains

Gold Myr

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

To Arms!

Untap all creatures you control.
Draw a card.

Drumbellower

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

Goblin Sharpshooter

Goblin Sharpshooter doesn't untap during your untap step.
Whenever a creature dies, untap Goblin Sharpshooter.
{T}: Goblin Sharpshooter deals 1 damage to any target.

Scaretiller

Whenever Scaretiller becomes tapped, choose one —
• You may put a land card from your hand onto the battlefield tapped.
• Return target land card from your graveyard to the battlefield tapped.

Stonybrook Schoolmaster

Whenever Stonybrook Schoolmaster becomes tapped, you may create a 1/1 blue Merfolk Wizard creature token.