Fabled Passage

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Haggle

You may discard a card. If you do, draw a card. (Then exile this card. You may cast the creature later from exile.)

Merchant of the Vale

Merchant of the Vale // Haggle

Arclight Phoenix

Flying, haste
At the beginning of combat on your turn, if you've cast three or more instant and sorcery spells this turn, return Arclight Phoenix from your graveyard to the battlefield.

Steam Vents

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

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Saheeli, Sublime Artificer

Whenever you cast a noncreature spell, create a 1/1 colorless Servo artifact creature token.
−2: Target artifact you control becomes a copy of another target artifact or creature you control until end of turn, except it's an artifact in addition to its other types.

Young Pyromancer

Whenever you cast an instant or sorcery spell, create a 1/1 red Elemental creature token.

Venture Deeper

Target player mills four cards. (Then exile this card. You may cast the creature later from exile.)

Merfolk Secretkeeper

Merfolk Secretkeeper // Venture Deeper

Spirebluff Canal

Spirebluff Canal enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {R}.