Brainstorm

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

Simic Signet

Arcane Signet

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

Breeding Pool

({T}: Add {G} or {U}.)
As Breeding Pool enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Command Tower

Talisman of Curiosity

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

Kinnan, Bonder Prodigy

Whenever you tap a nonland permanent for mana, add one mana of any type that permanent produced.
{5}{G}{U}: Look at the top five cards of your library. You may put a non-Human creature card from among them onto the battlefield. Put the rest on the bottom of your library in a random order.

Nyxbloom Ancient

Trample
If you tap a permanent for mana, it produces three times as much of that mana instead.

Koma, Cosmos Serpent

This spell can't be countered.
At the beginning of each upkeep, create a 3/3 blue Serpent creature token named Koma's Coil.
Sacrifice another Serpent: Choose one —
• Tap target permanent. Its activated abilities can't be activated this turn.
• Koma, Cosmos Serpent gains indestructible until end of turn.

Delighted Halfling

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a legendary spell, and that spell can't be countered.

Hullbreaker Horror

Flash
This spell can't be countered.
Whenever you cast a spell, choose up to one —
• Return target spell you don't control to its owner's hand.
• Return target nonland permanent to its owner's hand.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Basalt Monolith

Basalt Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{3}: Untap Basalt Monolith.

Fyndhorn Elves

Void Winnower

Your opponents can't cast spells with even mana values. (Zero is even.)
Your opponents can't block with creatures with even mana values.

Boseiju, Who Endures

{T}: Add {G}.
Channel — {1}{G}, Discard Boseiju, Who Endures: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

Birds of Paradise

Paradise Druid

Paradise Druid has hexproof as long as it's untapped. (It can't be the target of spells or abilities your opponents control.)
{T}: Add one mana of any color.

Worldly Tutor

Search your library for a creature card, reveal it, then shuffle and put the card on top.

Llanowar Elves

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Agatha's Soul Cauldron

You may spend mana as though it were mana of any color to activate abilities of creatures you control.
Creatures you control with +1/+1 counters on them have all activated abilities of all creature cards exiled with Agatha's Soul Cauldron.
{T}: Exile target card from a graveyard. When a creature card is exiled this way, put a +1/+1 counter on target creature you control.

Elvish Mystic

Eternal Witness

When Eternal Witness enters the battlefield, you may return target card from your graveyard to your hand.