Undercellar Sweep

When Undercellar Sweep enters, you take the initiative.
Whenever you attack, if you or a player you're attacking has the initiative, you create two 1/1 white Soldier creature tokens that are tapped and attacking.

Zhentarim Bandit

Whenever Zhentarim Bandit attacks, you may pay 1 life. If you do, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Coronation of Chaos

Up to three target creatures can't block this turn. Goad them. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Stirring Bard

Defender
When Stirring Bard enters, you take the initiative.
Mantle of Inspiration — {T}: Target creature gains menace and haste until end of turn.

Wyrm's Crossing Patrol

Myriad (Whenever this creature 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.)

Flaming Fist Officer

Whenever another creature you control leaves the battlefield, put a +1/+1 counter on Flaming Fist Officer.

Arms of Hadar

Creatures target player controls get -2/-2 until end of turn.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Sailors' Bane

This spell costs {1} less to cast for each card you own in exile and in your graveyard that's an instant card, a sorcery card, or a card that has an Adventure.
Ward {4} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {4}.)

Saddle of the Cavalier

Equipped creature gets +3/+3 and can't be blocked by creatures with power 3 or less.
Equip {3}

Web Shot

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

Ettercap

Ettercap // Web Shot

Split the Spoils

Exile up to five target permanent cards from your graveyard and separate them into two piles. An opponent chooses one of those piles. Put that pile into your hand and the other into your graveyard. (Piles can be empty.)

Lapis Orb of Dragonkind

{T}: Add {U}. When you spend this mana to cast a Dragon creature spell, 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.)

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

Tabaxi Toucaneers

Flying
Myriad (Whenever this creature 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.)

Predatory Impetus

Enchant creature
Enchanted creature gets +3/+3, must be blocked if able, and is goaded. (It attacks each combat if able and attacks a player other than you if able.)

Warehouse Thief

{2}, {T}, Sacrifice an artifact or creature: Exile the top card of your library. Until the end of your next turn, you may play that card.

Demonic Stench

Each creature that blocked this turn gets -1/-1 until end of turn. (Then exile this card. You may cast the creature later from exile.)

Hezrou

Whenever one or more creatures you control become blocked, each blocking creature gets -1/-1 until end of turn.

Hezrou // Demonic Stench

Aarakocra Sneak

Flying
When Aarakocra Sneak enters, you take the initiative.

Explosive Crystal

Explosive Crystal deals 4 damage divided as you choose among any number of targets. (Then exile this card. You may cast the creature later from exile.)

Amethyst Dragon

Amethyst Dragon // Explosive Crystal

Inspired Tinkering

Exile the top three cards of your library. Until the end of your next turn, you may play those cards.
Create three Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Astral Confrontation

This spell costs {1} less to cast for each opponent you're attacking.
Exile target creature.

Scouting Hawk

Flying
Keen Sight — When Scouting Hawk enters, if an opponent controls more lands than you, search your library for a basic Plains card, put it onto the battlefield tapped, then shuffle.

Dragonborn Looter

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

Dire Mimic

Flash
{T}, Sacrifice Dire Mimic: Add one mana of any color.
{3}: Dire Mimic becomes a Shapeshifter artifact creature with base power and toughness 5/5 until end of turn.

Beckoning Will-o'-Wisp

Flying
Lure the Unwary — At the beginning of combat on your turn, choose an opponent.
Creatures attacking the last chosen player get +1/+0.

Draconic Lore

This spell costs {2} less to cast if you control a Dragon.
Draw three cards.

Universal Solvent

{7}, {T}, Sacrifice Universal Solvent: Destroy target permanent.

Evolving Wilds

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

You're Confronted by Robbers

Choose one —
• Stall for Time — Tap up to three target creatures.
• Call for Aid — Create three 1/1 white Soldier creature tokens.

Mold Folk

Lifelink
Mold Harvest — {1}, Sacrifice another creature or an artifact: Put a +1/+1 counter on Mold Folk.

Underdark Explorer

Menace (This creature can't be blocked except by two or more creatures.)
When Underdark Explorer enters, you take the initiative.

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

Carnelian Orb of Dragonkind

{T}: Add {R}. If that mana is spent on a Dragon creature spell, it gains haste until end of turn.

Run Away Together

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

Forktail Sweep

Forktail Sweep deals 1 damage to each creature you don't control. (Then exile this card. You may cast the creature later from exile.)

Fang Dragon

Fang Dragon // Forktail Sweep

Summon Undead

You may mill three cards. Then return a creature card from your graveyard to the battlefield. (To mill a card, put the top card of your library into your graveyard.)

Chain Devil

Animate Chains — When Chain Devil enters, each player sacrifices a nontoken creature of their choice.

Javelin of Lightning

Flash
When Javelin of Lightning enters, attach it to target creature you control.
During your turn, equipped creature gets +2/+0 and has first strike.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

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.

Bag of Holding

Whenever you discard a card, exile that card from your graveyard.
{2}, {T}: Draw a card, then discard a card.
{4}, {T}, Sacrifice Bag of Holding: Return all cards exiled with Bag of Holding to their owner's hand.

Stunning Strike

Flash
Enchant creature
When Stunning Strike enters, tap enchanted creature and remove it from combat.
As long as enchanted creature isn't legendary, it doesn't untap during its controller's untap step.

Swashbuckler Extraordinaire

When Swashbuckler Extraordinaire enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Whenever you attack, you may sacrifice one or more Treasures. When you do, up to that many target creatures gain double strike until end of turn.

Reckless Barbarian

Sacrifice Reckless Barbarian: Add {R}{R}.

Contact Other Plane

Roll a d20.
1—9 | Draw two cards.
10—19 | Scry 2, then draw two cards.
20 | Scry 3, then draw three cards.

Jade Orb of Dragonkind

{T}: Add {G}. When you spend this mana to cast a Dragon creature spell, it enters with an additional +1/+1 counter on it and gains hexproof until your next turn. (It can't be the target of spells or abilities your opponents control.)

Explore the Underdark

Search your library for up to two basic land cards and/or Gate cards, put them onto the battlefield tapped, then shuffle.
You take the initiative.