Have

Counterspell

Training Center

This land enters tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Swords to Plowshares

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

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.")

Sea of Clouds

This land enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Veyran, Voice of Duality

Magecraft — Whenever you cast or copy an instant or sorcery spell, Veyran gets +1/+1 until end of turn.
If you casting or copying an instant or sorcery spell causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Kabira Evangel

Whenever this creature or another Ally you control enters, you may choose a color. If you do, Allies you control gain protection from the chosen color until end of turn.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Sokka's Charge

During your turn, Allies you control have double strike and lifelink.

Akoum Battlesinger

Haste
Whenever this creature or another Ally you control enters, you may have Ally creatures you control get +1/+0 until end of turn.

Sol Ring

Brainstorm

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

Katara, Water Tribe's Hope

Vigilance
When Katara enters, create a 1/1 white Ally creature token.
Waterbend {X}: Creatures you control have base power and toughness X/X until end of turn. X can't be 0. Activate only during your turn. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Hero of Goma Fada

Rally — Whenever this creature or another Ally you control enters, creatures you control gain indestructible until end of turn.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Redirect Lightning

As an additional cost to cast this spell, pay 5 life or pay {2}.
Change the target of target spell or ability with a single target.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Frostcliff Siege

As this enchantment enters, choose Jeskai or Temur.
• Jeskai — Whenever one or more creatures you control deal combat damage to a player, draw a card.
• Temur — Creatures you control get +1/+0 and have trample and haste.

Resolute Blademaster

Rally — Whenever this creature or another Ally you control enters, creatures you control gain double strike until end of turn.

Bender's Waterskin

Untap this artifact during each other player's untap step.
{T}: Add one mana of any color.

Arcane Signet

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

Jeskai Ascendancy

Whenever you cast a noncreature spell, creatures you control get +1/+1 until end of turn. Untap those creatures.
Whenever you cast a noncreature spell, you may draw a card. If you do, discard a card.

Crash Through

Creatures you control gain trample until end of turn. (Each of those creature can deal excess combat damage to the player or planeswalker it's attacking.)
Draw a card.

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.

Hakoda, Selfless Commander

Vigilance
You may look at the top card of your library any time.
You may cast Ally spells from the top of your library.
Sacrifice Hakoda: Creatures you control get +0/+5 and gain indestructible until end of turn.

Whirlwind of Thought

Whenever you cast a noncreature spell, draw a card.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Ondu Cleric

Whenever this creature or another Ally you control enters, you may gain life equal to the number of Allies you control.

United Front

Create X 1/1 white Ally creature tokens, then put a +1/+1 counter on each creature you control.

Sokka, Tenacious Tactician

Menace, prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Other Allies you control have menace and prowess.
Whenever you cast a noncreature spell, create a 1/1 white Ally creature token.