Witch's Clinic

{T}: Add {C}.
{2}, {T}: Target commander gains lifelink until end of turn.

Tyrant's Familiar

Flying, haste
Lieutenant — As long as you control your commander, Tyrant's Familiar gets +2/+2 and has "Whenever Tyrant's Familiar attacks, it deals 7 damage to target creature defending player controls."

Drillworks Mole

{2}, {T}: Put a +1/+1 counter on Drillworks Mole and a +1/+1 counter on up to one target commander creature you control.

Tome of Legends

Tome of Legends enters with a page counter on it.
Whenever your commander enters or attacks, put a page counter on Tome of Legends.
{1}, {T}, Remove a page counter from Tome of Legends: Draw a card.

Popular Entertainer

Commander creatures you own have "Whenever one or more creatures you control deal combat damage to a player, goad target creature that player controls." (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Passionate Archaeologist

Commander creatures you own have "Whenever you cast a spell from exile, this creature deals damage equal to that spell's mana value to target opponent."

Crimson Honor Guard

Trample
At the beginning of each player's end step, Crimson Honor Guard deals 4 damage to that player unless they control a commander.

Squee, the Immortal

You may cast Squee, the Immortal from your graveyard or from exile.

Bloodsworn Steward

Flying
Commander creatures you control get +2/+2 and have haste.

Loyal Apprentice

Haste
Lieutenant — At the beginning of combat on your turn, if you control your commander, create a 1/1 colorless Thopter artifact creature token with flying. That token gains haste until end of turn.

Dragon Cultist

Commander creatures you own have "At the beginning of your end step, if a source you controlled dealt 5 or more damage this turn, create a 4/4 red Dragon creature token with flying."

Skyfire Phoenix

Flying, haste
When you cast your commander, return Skyfire Phoenix from your graveyard to the battlefield.

Flamekin Herald

Commander spells you cast have cascade. (Whenever you cast a commander, exile cards from the top of your library until you exile a nonland card with lesser mana value. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Guild Artisan

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, you create two Treasure tokens." (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")