Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Deranged Assistant

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Strix Serenade

Counter target artifact, creature, or planeswalker spell. Its controller creates a 2/2 blue Bird creature token with flying.

Mistrise Village

This land enters tapped unless you control a Mountain or a Forest.
{T}: Add {U}.
{U}, {T}: The next spell you cast this turn can't be countered.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Hydro-Man, Fluid Felon

Whenever you cast a blue spell, if Hydro-Man is a creature, he gets +1/+1 until end of turn.
At the beginning of your end step, untap Hydro-Man. Until your next turn, he becomes a land and gains "{T}: Add {U}." (He's not a creature during that time.)

Island

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

Serum Visions

Siren Stormtamer

Flying
{U}, Sacrifice this creature: Counter target spell or ability that targets you or a creature you control.

Distortion Strike

Target creature gets +1/+0 until end of turn and can't be blocked this turn.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Brainstorm

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

Sol Ring

Defense Grid

Each spell costs {3} more to cast except during its controller's turn.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.