Lorwyn Eclipsed

Creature — Horse Serpent

This creature enters with three -1/-1 counters on it.
{1}{U}, Remove a counter from this creature: Draw a card.
{2}{U}, Remove two counters from this creature: Tap target creature. Put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Loch Mare

Creature — Elf Assassin

When this creature enters, target creature you control gets +X/+0 until end of turn and up to one target creature an opponent controls gets -0/-X until end of turn, where X is the number of Elves you control plus the number of Elf cards in your graveyard.

Gloom Ripper

Copy

Creature — Elf Cleric

When this creature enters, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Whenever one or more other creatures you control enter, if they entered or were cast from a graveyard, create a token that's a copy of one of them. This ability triggers only once each turn.