Alaborn Cavalier

Whenever this creature attacks, you may tap target creature.

Blinding Mage

Sol Ring

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}

Ballynock Trapper

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

Clever Distraction

Enchant creature
Enchanted creature has "Whenever this creature attacks, tap target creature defending player controls."
If Clever Distraction would be put into a graveyard from anywhere, exile it instead.

Distracting Geist

Whenever this creature attacks, tap target creature defending player controls.
Disturb {4}{W} (You may cast this card from your graveyard transformed for its disturb cost.)

Distracting Geist // Clever Distraction

Swords to Plowshares

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

Gideon's Lawkeeper

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.

Aysen Bureaucrats

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

Bola Slinger

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Whenever this creature attacks, tap target artifact or creature an opponent controls.

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.

Benalish Trapper

Bond of Discipline

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

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.)

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.

Plains

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.

Law-Rune Enforcer

{1}, {T}: Tap target creature with mana value 2 or greater.

Checkpoint Officer

Niblis of the Urn

Flying
Whenever this creature attacks, you may tap target creature.

Arashin Sunshield

When this creature enters, exile up to two target cards from a single graveyard.
{W}, {T}: Tap target creature.

Akroan Jailer

Githzerai Monk

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

Greatsword of Tyr

Whenever equipped creature attacks, put a +1/+1 counter on it and tap up to one target creature defending player controls.
Equip {W} ({W}: Attach to target creature you control. Equip only as a sorcery.)

Goldmeadow Harrier

Dawnglare Invoker

Flying
{8}: Tap all creatures target player controls.

Cloud, Midgar Mercenary

When Cloud enters, search your library for an Equipment card, reveal it, put it into your hand, then shuffle.
As long as Cloud is equipped, if an ability of Cloud or an Equipment attached to it triggers, that ability triggers an additional time.

Arcane Signet

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

Avacynian Priest

Stroke of Midnight

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

Master Decoy

Mind Stone

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

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.

Court Street Denizen

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