High Perfect Morcant

Whenever High Perfect Morcant or another Elf you control enters, each opponent blights 1. (They each put a -1/-1 counter on a creature they control.)
Tap three untapped Elves you control: Proliferate. Activate only as a sorcery. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Kithkin

Kithkeeper

Vivid — When this creature enters, create X 1/1 green and white Kithkin creature tokens, where X is the number of colors among permanents you control.
Tap three untapped creatures you control: This creature gets +3/+0 and gains flying until end of turn.

Hovel Hurler

This creature enters with two -1/-1 counters on it.
{R/W}{R/W}, Remove a counter from this creature: Another target creature you control gets +1/+0 and gains flying until end of turn. Activate only as a sorcery.

Kirol, Attentive First-Year

Tap two untapped creatures you control: Copy target triggered ability you control. You may choose new targets for the copy. Activate only once each turn.

Worm

Lluwen, Imperfect Naturalist

When Lluwen enters, mill four cards, then you may put a creature or land card from among the milled cards on top of your library.
{2}{B/G}{B/G}{B/G}, {T}, Discard a land card: Create a 1/1 black and green Worm creature token for each land card in your graveyard.

Maralen, Fae Ascendant

Flying
Whenever Maralen or another Elf or Faerie you control enters, exile the top two cards of target opponent's library.
Once each turn, you may cast a spell with mana value less than or equal to the number of Elves and Faeries you control from among cards exiled with Maralen this turn without paying its mana cost.

Merfolk

Merrow Skyswimmer

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Flying, vigilance
When this creature enters, create a 1/1 white and blue Merfolk creature token.

Mischievous Sneakling

Changeling (This card is every creature type.)
Flash

Morcant's Loyalist

Other Elves you control get +1/+1.
When this creature dies, return another target Elf card from your graveyard to your hand.

Treasure

Noggle Robber

When this creature enters or dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Prideful Feastling

Changeling (This card is every creature type.)
Lifelink

Raiding Schemes

Each noncreature spell you cast has conspire. (As you cast a noncreature spell, you may tap two untapped creatures you control that share a color with it. When you do, copy it and you may choose new targets for the copy. A copy of a permanent spell becomes a token.)

Liminal Hold

When this enchantment enters, exile up to one target nonland permanent an opponent controls until this enchantment leaves the battlefield. You gain 2 life.

Reaping Willow

Lifelink
This creature enters with two -1/-1 counters on it.
{1}{W/B}, Remove two counters from this creature: Return target creature card with mana value 3 or less from your graveyard to the battlefield. Activate only as a sorcery.

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.

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.

Lorwyn Eclipsed