Simic Growth Chamber

Simic Growth Chamber enters the battlefield tapped.
When Simic Growth Chamber enters the battlefield, return a land you control to its owner's hand.
{T}: Add {G}{U}.

Drowned Rusalka

{U}, Sacrifice a creature: Discard a card, then draw a card.

Surveilling Sprite

Flying
When Surveilling Sprite dies, you may draw a card.

Silkwing Scout

Flying
{G}, Sacrifice Silkwing Scout: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Simic Basilisk

Graft 3 (This creature enters the battlefield with three +1/+1 counters on it. Whenever another creature enters the battlefield, you may move a +1/+1 counter from this creature onto it.)
{1}{G}: Until end of turn, target creature with a +1/+1 counter on it gains "Whenever this creature deals combat damage to a creature, destroy that creature at end of combat."

Starved Rusalka

{G}, Sacrifice a creature: You gain 1 life.

Simic Guildmage

({G/U} can be paid with either {G} or {U}.)
{1}{G}: Move a +1/+1 counter from target creature onto another target creature with the same controller.
{1}{U}: Attach target Aura attached to a permanent to another permanent with the same controller.

Island

Simic Initiate

Graft 1 (This creature enters the battlefield with a +1/+1 counter on it. Whenever another creature enters the battlefield, you may move a +1/+1 counter from this creature onto it.)

Protean Hulk

When Protean Hulk dies, search your library for any number of creature cards with total mana value 6 or less, put them onto the battlefield, then shuffle.

Coiling Oracle

When Coiling Oracle enters the battlefield, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.

Experiment Kraj

Experiment Kraj has all activated abilities of each other creature with a +1/+1 counter on it.
{T}: Put a +1/+1 counter on target creature.

Novijen, Heart of Progress

{T}: Add {C}.
{G}{U}, {T}: Put a +1/+1 counter on each creature that entered the battlefield this turn.

Thrive

Put a +1/+1 counter on each of X target creatures.

Shielding Plax

({G/U} can be paid with either {G} or {U}.)
Enchant creature
When Shielding Plax enters the battlefield, draw a card.
Enchanted creature can't be the target of spells or abilities your opponents control.

Indrik Stomphowler

When Indrik Stomphowler enters the battlefield, destroy target artifact or enchantment.

Stasis Cell

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.
{3}{U}: Attach Stasis Cell to target creature.

Plaxmanta

Flash
When Plaxmanta enters the battlefield, creatures you control gain shroud until end of turn. (They can't be the targets of spells or abilities.)
When Plaxmanta enters the battlefield, sacrifice it unless {G} was spent to cast it.

Vigean Hydropon

Graft 5 (This creature enters the battlefield with five +1/+1 counters on it. Whenever another creature enters the battlefield, you may move a +1/+1 counter from this creature onto it.)
Vigean Hydropon can't attack or block.

Vigean Graftmage

Graft 2 (This creature enters the battlefield with two +1/+1 counters on it. Whenever another creature enters the battlefield, you may move a +1/+1 counter from this creature onto it.)
{1}{U}: Untap target creature with a +1/+1 counter on it.

Simic Ragworm

Flash Foliage

Cast this spell only during combat after blockers are declared.
Create a 1/1 green Saproling creature token that's blocking target creature attacking you.
Draw a card.

Helium Squirter

Graft 3 (This creature enters the battlefield with three +1/+1 counters on it. Whenever another creature enters the battlefield, you may move a +1/+1 counter from this creature onto it.)
{1}: Target creature with a +1/+1 counter on it gains flying until end of turn.