Champion of Rhonas

You may exert Champion of Rhonas as it attacks. When you do, you may put a creature card from your hand onto the battlefield. (An exerted creature won't untap during your next untap step.)

Flowering of the White Tree

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

Ahn-Crop Champion

You may exert Ahn-Crop Champion as it attacks. When you do, untap all other creatures you control. (An exerted creature won't untap during your next untap step.)

Karlach, Fury of Avernus

Whenever you attack, if it's the first combat phase of the turn, untap all attacking creatures. They gain first strike until end of turn. After this phase, there is an additional combat phase.
Choose a Background (You can have a Background as a second commander.)

Ahn-Crop Crasher

Haste (This creature can attack and {T} as soon as it comes under your control.)
You may exert Ahn-Crop Crasher as it attacks. When you do, target creature can't block this turn. (An exerted creature won't untap during your next untap step.)

Devoted Crop-Mate

You may exert Devoted Crop-Mate as it attacks. When you do, return target creature card with mana value 2 or less from your graveyard to the battlefield. (An exerted creature won't untap during your next untap step.)

General Ferrous Rokiric

Hexproof from monocolored
Whenever you cast a multicolored spell, create a 4/4 red and white Golem artifact creature token.

Themberchaud

Trample
When Themberchaud enters, he deals X damage to each other creature without flying and each player, where X is the number of Mountains you control.
You may exert Themberchaud as he attacks. When you do, he gains flying until end of turn. (An exerted creature won't untap during your next untap step.)

Rising of the Day

Creatures you control have haste.
Legendary creatures you control get +1/+0.

Resolute Survivors

You may exert Resolute Survivors as it attacks. (It won't untap during your next untap step.)
Whenever you exert a creature, Resolute Survivors deals 1 damage to each opponent and you gain 1 life.

Jetmir, Nexus of Revels

Creatures you control get +1/+0 and have vigilance as long as you control three or more creatures.
Creatures you control also get +1/+0 and have trample as long as you control six or more creatures.
Creatures you control also get +1/+0 and have double strike as long as you control nine or more creatures.

Moraug, Fury of Akoum

Each creature you control gets +1/+0 for each time it has attacked this turn.
Landfall — Whenever a land you control enters, if it's your main phase, there's an additional combat phase after this phase. At the beginning of that combat, untap all creatures you control.

Fallaji Wayfarer

Fallaji Wayfarer is all colors. This ability doesn't affect its color identity. (It can be in any deck whose commander's color identity includes green.)
Multicolored spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting a multicolored spell pays for {1} or one mana of a color that creature is.)

Brave the Sands

Creatures you control have vigilance.
Each creature you control can block an additional creature each combat.

Rohirrim Chargers

You may exert Rohirrim Chargers as it attacks. (It won't untap during your next untap step.)
Whenever you exert a creature, reveal cards from the top of your library until you reveal an Equipment card. Put that card onto the battlefield attached to that creature, then put the rest on the bottom of your library in a random order.

Combat Celebrant

If Combat Celebrant hasn't been exerted this turn, you may exert it as it attacks. When you do, untap all other creatures you control and after this phase, there is an additional combat phase. (An exerted creature won't untap during your next untap step.)

Resurgence

Creatures you control gain first strike and vigilance until end of turn. After this main phase, there is an additional combat phase followed by an additional main phase.

Response

Response deals 5 damage to target attacking or blocking creature.

Response // Resurgence

Always Watching

Nontoken creatures you control get +1/+1 and have vigilance.

Vizier of the True

You may exert Vizier of the True as it attacks. (It won't untap during your next untap step.)
Whenever you exert a creature, tap target creature an opponent controls.

Glorybringer

Flying, haste
You may exert Glorybringer as it attacks. When you do, it deals 4 damage to target non-Dragon creature an opponent controls. (An exerted creature won't untap during your next untap step.)

Savage Beating

Cast this spell only during your turn and only during combat.
Choose one —
• Creatures you control gain double strike until end of turn.
• Untap all creatures you control. After this phase, there is an additional combat phase.
Entwine {1}{R} (Choose both if you pay the entwine cost.)

Johan

At the beginning of combat on your turn, you may have Johan gain "Johan can't attack" until end of combat. If you do, attacking doesn't cause creatures you control to tap this combat if Johan is untapped.

Bloodthirster

Flying, trample
Whenever Bloodthirster deals combat damage to a player, untap it. After this phase, there is an additional combat phase.
Bloodthirster can't attack a player it has already attacked this turn.

Tah-Crop Elite

Flying
You may exert Tah-Crop Elite as it attacks. When you do, creatures you control get +1/+1 until end of turn. (An exerted creature won't untap during your next untap step.)

Battlefield Scavenger

You may exert Battlefield Scavenger as it attacks. (It won't untap during your next untap step.)
Whenever you exert a creature, you may discard a card. If you do, draw a card.

Watchful Naga

You may exert Watchful Naga as it attacks. When you do, draw a card. (An exerted creature won't untap during your next untap step.)

Purphoros, Bronze-Blooded

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Other creatures you control have haste.
{2}{R}: You may put a red creature card or an artifact creature card from your hand onto the battlefield. Sacrifice it at the beginning of the next end step.

Trueheart Twins

You may exert Trueheart Twins as it attacks. (It won't untap during your next untap step.)
Whenever you exert a creature, creatures you control get +1/+0 until end of turn.

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.