Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Azami, Lady of Scrolls

Tap an untapped Wizard you control: Draw a card.

Master of the Pearl Trident

Other Merfolk creatures you control get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)

Elvish Champion

Other Elf creatures get +1/+1 and have forestwalk. (They can't be blocked as long as defending player controls a Forest.)

Simic Signet

Muscle Sliver

Lilysplash Mentor

Reach
{1}{G}{U}: Exile another target creature you control, then return it to the battlefield under its owner's control with a +1/+1 counter on it. Activate only as a sorcery.

Whelming Wave

Return all creatures to their owners' hands except for Krakens, Leviathans, Octopuses, and Serpents.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Lord of the Unreal

Illusion creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Venom Sliver

Sliver creatures you control have deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Diffusion Sliver

Whenever a Sliver creature you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {2}.

Megantic Sliver

Timber Protector

Other Treefolk creatures you control get +1/+1.
Other Treefolk and Forests you control have indestructible.

Thassa, Deep-Dwelling

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature.
At the beginning of your end step, exile up to one other target creature you control, then return that card to the battlefield under your control.
{3}{U}: Tap another target creature.

Teferi's Time Twist

Exile target permanent you control. Return that card to the battlefield under its owner's control at the beginning of the next end step. If it enters as a creature, it enters with an additional +1/+1 counter on it.

Pheres-Band Warchief

Vigilance, trample
Other Centaur creatures you control get +1/+1 and have vigilance and trample.

Greatbow Doyen

Other Archer creatures you control get +1/+1.
Whenever an Archer you control deals damage to a creature, that Archer deals that much damage to that creature's controller.

Winged Sliver

Might Sliver

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Horned Sliver

Splash Portal

Exile target creature you control, then return it to the battlefield under its owner's control. If that creature is a Bird, Frog, Otter, or Rat, draw a card.

Virulent Sliver

All Sliver creatures have poisonous 1. (Whenever a Sliver deals combat damage to a player, that player gets a poison counter. A player with ten or more poison counters loses the game.)

Omo, Queen of Vesuva

Whenever Omo, Queen of Vesuva enters or attacks, put an everything counter on each of up to one target land and up to one target creature.
Each land with an everything counter on it is every land type in addition to its other types.
Each nonland creature with an everything counter on it is every creature type.

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.

Sol Ring

Elvish Archdruid

Other Elf creatures you control get +1/+1.
{T}: Add {G} for each Elf you control.

Talisman of Curiosity

{T}: Add {C}.
{T}: Add {G} or {U}. Talisman of Curiosity deals 1 damage to you.

Gemhide Sliver

All Slivers have "{T}: Add one mana of any color."

Myr Galvanizer

Other Myr creatures you control get +1/+1.
{1}, {T}: Untap each other Myr you control.

Shifting Sliver

Slivers can't be blocked except by Slivers.

Mass Appeal

Dwynen, Gilt-Leaf Daen

Reach (This creature can block creatures with flying.)
Other Elf creatures you control get +1/+1.
Whenever Dwynen attacks, you gain 1 life for each attacking Elf you control.

Aggressive Biomancy

Create X tokens that are copies of target creature you control, except they have "When this creature enters, it fights up to one target creature you don't control."