Hero's Blade

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

Loyal Unicorn

Vigilance
Lieutenant — At the beginning of combat on your turn, if you control your commander, prevent all combat damage that would be dealt to creatures you control this turn. Other creatures you control gain vigilance until end of turn.

Keleth, Sunmane Familiar

Whenever a commander you control attacks, put a +1/+1 counter on it.
Partner (You can have two commanders if both have partner.)

Mother of Runes

{T}: Target creature you control gains protection from the color of your choice until end of turn.

Blind Obedience

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Artifacts and creatures your opponents control enter the battlefield tapped.

Bastion Protector

Commander creatures you control get +2/+2 and have indestructible.

Commander's Plate

Equipped creature gets +3/+3 and has protection from each color that's not in your commander's color identity.
Equip commander {3}
Equip {5}

Commander's Insignia

Creatures you control get +1/+1 for each time you've cast your commander from the command zone this game.

Keeper of the Accord

At the beginning of each opponent's end step, if that player controls more creatures than you, create a 1/1 white Soldier creature token.
At the beginning of each opponent's end step, if that player controls more lands than you, you may search your library for a basic Plains card, put it onto the battlefield tapped, then shuffle.

Angelic Field Marshal

Flying
Lieutenant — As long as you control your commander, Angelic Field Marshal gets +2/+2 and creatures you control have vigilance.

Secluded Steppe

Secluded Steppe enters the battlefield tapped.
{T}: Add {W}.
Cycling {W} ({W}, Discard this card: Draw a card.)

Settle the Wreckage

Exile all attacking creatures target player controls. That player may search their library for that many basic land cards, put those cards onto the battlefield tapped, then shuffle.

Timely Ward

You may cast Timely Ward as though it had flash if it targets a commander.
Enchant creature
Enchanted creature has indestructible.

Eiganjo Castle

{T}: Add {W}.
{W}, {T}: Prevent the next 2 damage that would be dealt to target legendary creature this turn.

Slash the Ranks

Destroy all creatures and planeswalkers except for commanders.

Sun Titan

Vigilance
Whenever Sun Titan enters the battlefield or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

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}

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.

Command Tower

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

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.

Grasp of Fate

When Grasp of Fate enters the battlefield, for each opponent, exile up to one target nonland permanent that player controls until Grasp of Fate leaves the battlefield. (Those permanents return under their owners' control.)

Plains

Thriving Heath

Thriving Heath enters the battlefield tapped.
As Thriving Heath enters the battlefield, choose a color other than white.
{T}: Add {W} or one mana of the chosen color.