Dragon Tempest

Whenever a creature you control with flying enters, it gains haste until end of turn.
Whenever a Dragon you control enters, it deals X damage to any target, where X is the number of Dragons you control.

Sol Ring

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Orthion, Hero of Lavabrink

{1}{R}, {T}: Create a token that's a copy of another target creature you control. It gains haste. Sacrifice it at the beginning of the next end step. Activate only as a sorcery.
{6}{R}{R}{R}, {T}: Create five tokens that are copies of another target creature you control. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Watery Grave

({T}: Add {U} or {B}.)
As Watery Grave enters, you may pay 2 life. If you don't, it enters tapped.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Arcane Signet

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

Bident of Thassa

Whenever a creature you control deals combat damage to a player, you may draw a card.
{1}{U}, {T}: Creatures your opponents control attack this turn if able.

Xander's Lounge

({T}: Add {U}, {B}, or {R}.)
Xander's Lounge enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Thousand-Faced Shadow

Ninjutsu {2}{U}{U} ({2}{U}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Flying
When Thousand-Faced Shadow enters from your hand, if it's attacking, create a token that's a copy of another target attacking creature. The token enters tapped and attacking.

Blade of Selves

Equipped creature has myriad. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Equip {4}

Mountain

Fellwar Stone

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

Exotic Orchard

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Counterspell

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Prosperous Thief

Ninjutsu {1}{U} ({1}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever one or more Ninja or Rogue creatures you control deal combat damage to a player, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Grim Hireling

Whenever one or more creatures you control deal combat damage to a player, create two Treasure tokens.
{B}, Sacrifice X Treasures: Target creature gets -X/-X until end of turn. Activate only as a sorcery.

Nashi, Moon Sage's Scion

Ninjutsu {3}{B} ({3}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Nashi, Moon Sage's Scion deals combat damage to a player, exile the top card of each player's library. Until end of turn, you may play one of those cards. If you cast a spell this way, pay life equal to its mana value rather than paying its mana cost.

Talisman of Creativity

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

Phoenix Chick

Flying, haste
Phoenix Chick can't block.
Whenever you attack with three or more creatures, you may pay {R}{R}. If you do, return Phoenix Chick from your graveyard to the battlefield tapped and attacking with a +1/+1 counter on it.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

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.

Moon-Circuit Hacker

Ninjutsu {U} ({U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Moon-Circuit Hacker deals combat damage to a player, you may draw a card. If you do, discard a card unless Moon-Circuit Hacker entered this turn.

Reconnaissance Mission

Whenever a creature you control deals combat damage to a player, you may draw a card.
Cycling {2} ({2}, Discard this card: Draw a card.)

Changeling Outcast

Changeling (This card is every creature type.)
Changeling Outcast can't block and can't be blocked.

Island

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Command Tower

Grazilaxx, Illithid Scholar

Whenever a creature you control becomes blocked, you may return it to its owner's hand.
Whenever one or more creatures you control deal combat damage to a player, draw a card.

Kaito, Dancing Shadow

Whenever one or more creatures you control deal combat damage to a player, you may return one of them to its owner's hand. If you do, you may activate loyalty abilities of Kaito twice this turn rather than only once.
+1: Up to one target creature can't attack or block until your next turn.
0: Draw a card.
−2: Create a 2/2 colorless Drone artifact creature token with deathtouch and "When this creature leaves the battlefield, each opponent loses 2 life and you gain 2 life."

Terminate

Destroy target creature. It can't be regenerated.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

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.)

Negate

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.

Goro-Goro and Satoru

Whenever one or more creatures you control that entered this turn deal combat damage to a player, create a 5/5 red Dragon Spirit creature token with flying.
{1}{R}: Creatures you control gain haste until end of turn.

Swamp

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters, you may pay 2 life. If you don't, it enters tapped.

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters, you may pay 2 life. If you don't, it enters tapped.

Faerie Mastermind

Flash
Flying
Whenever an opponent draws their second card each turn, you draw a card.
{3}{U}: Each player draws a card.

Urabrask's Forge

At the beginning of combat on your turn, put an oil counter on Urabrask's Forge, then create an X/1 red Phyrexian Horror creature token with trample and haste, where X is the number of oil counters on Urabrask's Forge. Sacrifice that token at the beginning of the next end step.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Professional Face-Breaker

Menace
Whenever one or more creatures you control deal combat damage to a player, create a Treasure token.
Sacrifice a Treasure: Exile the top card of your library. You may play that card this turn.

Jeska's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Add {R} for each card in target opponent's hand.
• Exile the top three cards of your library. You may play them this turn.