Flowering of the White Tree

Legendary creatures you control get +2/+1 and have ward {1}.
Nonlegendary creatures you control get +1/+1.

Leonin Elder

Whenever an artifact enters, you may gain 1 life.

Mithril Coat

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}

D'Avenant Trapper

Whenever you cast a historic spell, tap target creature an opponent controls. (Artifacts, legendaries, and Sagas are historic.)

Daring Archaeologist

When Daring Archaeologist enters, you may return target artifact card from your graveyard to your hand.
Whenever you cast a historic spell, put a +1/+1 counter on Daring Archaeologist. (Artifacts, legendaries, and Sagas are historic.)

Avacyn's Memorial

Indestructible
Other legendary permanents you control have indestructible.

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.

You Cannot Pass!

Destroy target creature that blocked or was blocked by a legendary creature this turn.

Layla Hassan

First strike
When Layla Hassan enters and whenever one or more Assassins you control deal combat damage to a player, return target historic card from your graveyard to your hand.

Andúril, Flame of the West

Equipped creature gets +3/+1.
Whenever equipped creature attacks, create two tapped 1/1 white Spirit creature tokens with flying. If that creature is legendary, instead create two of those tokens that are tapped and attacking.
Equip {2}

Hero's Blade

Equipped creature gets +3/+2.
Whenever a legendary creature you control enters, you may attach Hero's Blade to it.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

Benalish Honor Guard

Benalish Honor Guard gets +1/+0 for each legendary creature you control.

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Sol Ring

Roaming Throne

Ward {2}
As Roaming Throne enters, choose a creature type.
Roaming Throne is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Bessie, the Doctor's Roadster

Haste
Whenever Bessie attacks, another target legendary creature can't be blocked this turn.
Crew 2 (Tap any number of creatures you control with total power 2 or more: This Vehicle becomes an artifact creature until end of turn.)

Loyal Retainers

Sacrifice Loyal Retainers: Return target legendary creature card from your graveyard to the battlefield. Activate only during your turn, before attackers are declared.

Crown of Gondor

Equipped creature gets +1/+1 for each creature you control.
When a legendary creature you control enters, if there is no monarch, you become the monarch.
Equip {4}. This ability costs {3} less to activate if you're the monarch.

Delney, Streetwise Lookout

Creatures you control with power 2 or less can't be blocked by creatures with power 3 or greater.
If an ability of a creature you control with power 2 or less triggers, that ability triggers an additional time.

Confession Dial

When Confession Dial enters, surveil 3.
{T}: Target legendary creature card in your graveyard gains escape until end of turn. The escape cost is equal to its mana cost plus exile three other cards from your graveyard. (You may cast it from your graveyard for its escape cost this turn.)

Sculpting Steel

You may have Sculpting Steel enter as a copy of any artifact on the battlefield.

Vedalken Orrery

You may cast spells as though they had flash.

Mox Amber

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

Liberator, Urza's Battlethopter

Flash
Flying
You may cast colorless spells and artifact spells as though they had flash.
Whenever you cast a spell, if the amount of mana spent to cast that spell is greater than Liberator, Urza's Battlethopter's power, put a +1/+1 counter on Liberator.

Banish to Another Universe

Affinity for historic permanents (This spell costs {1} less to cast for each artifact, legendary, and/or Saga permanent you control.)
When Banish to Another Universe enters, exile target nonland permanent an opponent controls until Banish to Another Universe leaves the battlefield.

Shimmer Myr

Flash
You may cast artifact spells as though they had flash.

Sarah Jane Smith

Whenever you cast a historic spell, investigate. This ability triggers only once each turn. (Artifacts, legendaries, and Sagas are historic. To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Doctor's companion (You can have two commanders if the other is the Doctor.)

Sigarda's Aid

You may cast Aura and Equipment spells as though they had flash.
Whenever an Equipment you control enters, you may attach it to target creature you control.

Champion's Helm

Equipped creature gets +2/+2.
As long as equipped creature is legendary, it has hexproof. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Hero's Heirloom

Equipped creature gets +2/+1.
As long as equipped creature is legendary, it has trample and haste.
Equip {2}

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Pearl Medallion

White spells you cast cost {1} less to cast.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Skittering Cicada

Flash
You may cast colorless spells as though they had flash.
Whenever you cast a colorless spell, until end of turn, Skittering Cicada gains trample and gets +X/+X, where X is that spell's mana value.

Ingenious Smith

When Ingenious Smith enters, look at the top four cards of your library. You may reveal an artifact card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Whenever one or more artifacts you control enter, put a +1/+1 counter on Ingenious Smith. This ability triggers only once each turn.

Yoshimaru, Ever Faithful

Whenever another legendary permanent you control enters, put a +1/+1 counter on Yoshimaru, Ever Faithful.
Partner (You can have two commanders if both have partner.)

Gandalf the White

Flash
You may cast legendary spells and artifact spells as though they had flash.
If a legendary permanent or an artifact entering or leaving the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Arcane Signet

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

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

Loran, Disciple of History

Whenever Loran, Disciple of History or another legendary creature you control enters, return target artifact card from your graveyard to your hand.