Sanguine Syphoner

Whenever this creature attacks, each opponent loses 1 life and you gain 1 life.

Etali, Primal Storm

Whenever Etali attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Isshin, Two Heavens as One

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

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Quick-Draw Katana

During your turn, equipped creature gets +2/+0 and has first strike. (It deals combat damage before creatures without first strike.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Sword of the Animist

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {2}

Arabella, Abandoned Doll

Whenever Arabella, Abandoned Doll attacks, it deals X damage to each opponent and you gain X life, where X is the number of creatures you control with power 2 or less.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Arcane Signet

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

Boros Signet

Mountain

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Swamp

Swords to Plowshares

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

Krenko, Tin Street Kingpin

Whenever Krenko, Tin Street Kingpin attacks, put a +1/+1 counter on it, then create a number of 1/1 red Goblin creature tokens equal to Krenko's power.

Command Tower

Audacious Thief

Whenever Audacious Thief attacks, you draw a card and you lose 1 life.

Plains

Nomad Outpost

Nomad Outpost enters tapped.
{T}: Add {R}, {W}, or {B}.

Brutal Hordechief

Whenever a creature you control attacks, defending player loses 1 life and you gain 1 life.
{3}{R/W}{R/W}: Creatures your opponents control block this turn if able, and you choose how those creatures block.

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. Talisman of Conviction deals 1 damage to you.

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.

Alesha, Who Laughs at Fate

First strike
Whenever Alesha attacks, put a +1/+1 counter on it.
Raid — At the beginning of your end step, if you attacked this turn, return target creature card with mana value less than or equal to Alesha's power from your graveyard to the battlefield.