Deepway Navigator

Flash
When this creature enters, untap each other Merfolk you control.
As long as you attacked with three or more Merfolk this turn, Merfolk you control get +1/+0.

Dawnhand Dissident

{T}, Blight 1: Surveil 1.
{T}, Blight 2: Exile target card from a graveyard.
During your turn, you may cast creature spells from among cards you own exiled with this creature by removing three counters from among creatures you control in addition to paying their other costs.

Sanar, Innovative First-Year

Vivid — At the beginning of your first main phase, reveal cards from the top of your library until you reveal X nonland cards, where X is the number of colors among permanents you control. For each of those colors, you may exile a card of that color from among the revealed cards. Then shuffle. You may cast the exiled cards this turn.

Champion of the Path

As an additional cost to cast this spell, behold an Elemental and exile it. (Exile an Elemental you control or an Elemental card from your hand.)
Whenever another Elemental you control enters, it deals damage equal to its power to each opponent.
When this creature leaves the battlefield, return the exiled card to its owner's hand.

Temple Garden

({T}: Add {G} or {W}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Rimefire Torque

As this artifact enters, choose a creature type.
Whenever a permanent you control of the chosen type enters, put a charge counter on this artifact.
{T}, Remove three charge counters from this artifact: When you next cast an instant or sorcery spell this turn, copy it. You may choose new targets for the copy.

Adept Watershaper

Other tapped creatures you control have indestructible.

Thousand-Year Elixir

You may activate abilities of creatures you control as though those creatures had haste.
{1}, {T}: Untap target creature.

Bre of Clan Stoutarm

{1}{W}, {T}: Another target creature you control gains flying and lifelink until end of turn.
At the beginning of your end step, if you gained life this turn, exile cards from the top of your library until you exile a nonland card. You may cast that card without paying its mana cost if the spell's mana value is less than or equal to the amount of life you gained this turn. Otherwise, put it into your hand.

Vibrance

When this creature enters, if {R}{R} was spent to cast it, this creature deals 3 damage to any target.
When this creature enters, if {G}{G} was spent to cast it, search your library for a land card, reveal it, put it into your hand, then shuffle. You gain 2 life.
Evoke {R/G}{R/G}

Shadow Urchin

Whenever this creature attacks, blight 1. (Put a -1/-1 counter on a creature you control.)
Whenever a creature you control with one or more counters on it dies, exile that many cards from the top of your library. Until your next end step, you may play those cards.

Champions of the Shoal

As an additional cost to cast this spell, behold a Merfolk and exile it. (Exile a Merfolk you control or a Merfolk card from your hand.)
Whenever this creature enters or becomes tapped, tap up to one target creature and put a stun counter on it.
When this creature leaves the battlefield, return the exiled card to its owner's hand.