Consider

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

Mystical Dispute

This spell costs {2} less to cast if it targets a blue spell.
Counter target spell unless its controller pays {3}.

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

Murkwater Pathway

Clearwater Pathway

Clearwater Pathway // Murkwater Pathway

Darkslick Shores

Darkslick Shores enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

No One Left Behind

This spell costs {3} less to cast if it targets a creature card with mana value 3 or less.
Return target creature card from your graveyard to the battlefield.

Vanishing Verse

Cryptic Coat

When Cryptic Coat enters, cloak the top card of your library, then attach Cryptic Coat to it. (To cloak a card, put it onto the battlefield face down as a 2/2 creature with ward {2}. Turn it face up any time for its mana cost if it's a creature card.)
Equipped creature gets +1/+0 and can't be blocked.
{1}{U}: Return Cryptic Coat to its owner's hand.

Pest Control

Destroy all nonland permanents with mana value 1 or less.
Cycling {2} ({2}, Discard this card: Draw a card.)

Geralf, the Fleshwright

Whenever you cast a spell during your turn other than your first spell that turn, create a 2/2 blue and black Zombie Rogue creature token.
Whenever a Zombie you control enters, put a +1/+1 counter on it for each other Zombie that entered the battlefield under your control this turn.

Go Blank

Target player discards two cards. Then exile that player's graveyard.

Free the Fae

Mill four cards. Then put an instant, sorcery, or Faerie card from among the milled cards into your hand.

Picklock Prankster

Picklock Prankster // Free the Fae

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.

Ashiok, Dream Render

Spells and abilities your opponents control can't cause their controller to search their library.
−1: Target player mills four cards. Then exile each opponent's graveyard.

Negate

Watery Grave

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

Stormcarved Coast

Stormcarved Coast enters tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Treasure Cruise

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

Bitter Triumph

As an additional cost to cast this spell, discard a card or pay 3 life.
Destroy target creature or planeswalker.

Swamp

Satoru, the Infiltrator

Menace
Whenever Satoru, the Infiltrator and/or one or more other nontoken creatures you control enter, if none of them were cast or no mana was spent to cast them, draw a card.

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.

Hall of Storm Giants

If you control two or more other lands, Hall of Storm Giants enters tapped.
{T}: Add {U}.
{5}{U}: Until end of turn, Hall of Storm Giants becomes a 7/7 blue Giant creature with ward {3}. It's still a land. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)