Alaundo the Seer

{T}: Draw a card, then exile a card from your hand and put a number of time counters on it equal to its mana value. It gains "When the last time counter is removed from this card, if it's exiled, you may cast it without paying its mana cost. If you cast a creature spell this way, it gains haste until end of turn." Then remove a time counter from each other card you own in exile.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Vhal, Candlekeep Researcher

Vigilance
{T}: Add an amount of {C} equal to Vhal, Candlekeep Researcher's toughness. This mana can't be spent to cast spells from your hand.
Choose a Background (You can have a Background as a second commander.)

Bane's Contingency

Counter target spell. If that spell targets a commander you control, instead counter that spell, scry 2, then draw a card.

Sand Augury

Scry 1, then draw a card. (Then exile this card. You may cast the creature later from exile.)

Young Blue Dragon

Young Blue Dragon // Sand Augury

Dream Fracture

Counter target spell. Its controller draws a card.
Draw a card.

Band Together

Up to two target creatures you control each deal damage equal to their power to another target creature.

Island

Master Chef

Commander creatures you own have "This creature enters with an additional +1/+1 counter on it" and "Other creatures you control enter with an additional +1/+1 counter on them."

Avenging Hunter

Trample
When Avenging Hunter enters, you take the initiative.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Capsizing Wave

Return target creature to its owner's hand. (Then exile this card. You may cast the creature later from exile.)

Sword Coast Serpent

Sword Coast Serpent can't be blocked as long as you've cast a noncreature spell this turn.

Sword Coast Serpent // Capsizing Wave

Sea Gate

Sea Gate enters tapped.
As Sea Gate enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Manor Gate

Manor Gate enters tapped.
As Manor Gate enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Aquatic Ingress

Up to two target creatures each get +1/+0 until end of turn and can't be blocked this turn. (Then exile this card. You may cast the creature later from exile.)

Sea Hag

When Sea Hag enters, creatures your opponents control get -4/-0 until end of turn.

Sea Hag // Aquatic Ingress

Ambitious Dragonborn

Ambitious Dragonborn enters with X +1/+1 counters on it, where X is the greatest power among creatures you control and creature cards in your graveyard.

Dragonborn Looter

{1}, {T}: Draw a card, then discard a card.

Scale Deflection

Put two +1/+1 counters on target creature and untap it. It gains hexproof until end of turn. (Then exile this card. You may cast the creature later from exile.)

Dread Linnorm

Dread Linnorm can't be blocked by creatures with power 3 or less.

Dread Linnorm // Scale Deflection

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Undercellar Myconid

When Undercellar Myconid enters or dies, create a 1/1 green Saproling creature token.
{T}: Add one mana of any color.

Forest

Tomb of Horrors Adventurer

When Tomb of Horrors Adventurer enters, you take the initiative.
Whenever you cast your second spell each turn, copy it. If you've completed a dungeon, copy that spell twice instead. You may choose new targets for the copies. (A copy of a permanent spell becomes a token.)

Korlessa, Scale Singer

You may look at the top card of your library any time.
You may cast Dragon spells from the top of your library.

Carefree Swinemaster

Whenever Carefree Swinemaster attacks, you may pay {1}{G}. If you do, create a 2/2 green Boar creature token that's tapped and attacking.

Aarakocra Sneak

Flying
When Aarakocra Sneak enters, you take the initiative.

Volo, Itinerant Scholar

When Volo enters, create Volo's Journal, a legendary colorless artifact token with hexproof and "Whenever you cast a creature spell, note one of its creature types that hasn't been noted for this artifact."
{2}, {T}: Draw a card for each creature type noted for target permanent you control named Volo's Journal.
Choose a Background

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Skullwinder

Deathtouch
When Skullwinder enters, return target card from your graveyard to your hand, then choose an opponent. That player returns a card from their graveyard to their hand.

Scaled Nurturer

{T}: Add {G}. When you spend this mana to cast a Dragon creature spell, you gain 2 life.

Cone of Cold

Roll a d20.
1—9 | Tap all creatures your opponents control.
10—19 | Tap all creatures your opponents control. Those creatures don't untap during their controllers' next untap steps.
20 | Tap all creatures your opponents control. Those creatures don't untap during their controllers' next untap steps. Until your next turn, creatures your opponents control enter tapped.

Arcane Signet

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

Web Shot

Destroy target creature with flying. (Then exile this card. You may cast the creature later from exile.)

Ettercap

Ettercap // Web Shot

Druid of the Emerald Grove

When Druid of the Emerald Grove enters, search your library for up to two basic land cards and reveal them, then roll a d20.
9 or less | Put those cards into your hand, then shuffle.
10—19 | Put one of those cards onto the battlefield tapped and the other into your hand, then shuffle.
20+ | Put those cards onto the battlefield tapped, then shuffle.