Goldnight Commander

Whenever another creature you control enters, creatures you control get +1/+1 until end of turn.

Galadriel, Light of Valinor

Alliance — Whenever another creature you control enters, choose one that hasn't been chosen this turn —
• Add {G}{G}{G}.
• Put a +1/+1 counter on each creature you control.
• Scry 2, then draw a card.

Celebrity Fencer

Alliance — Whenever another creature you control enters, put a +1/+1 counter on this creature.

Midnight Guard

Whenever another creature enters, untap this creature.

Elegant Entourage

Alliance — Whenever another creature you control enters, target creature other than this creature gets +1/+1 and gains trample until end of turn.

Venom Connoisseur

Alliance — Whenever another creature you control enters, this creature gains deathtouch until end of turn. If this is the second time this ability has resolved this turn, all creatures you control gain deathtouch until end of turn.

Champion of Lambholt

Creatures with power less than this creature's power can't block creatures you control.
Whenever another creature you control enters, put a +1/+1 counter on this creature.

Gala Greeters

Alliance — Whenever another creature you control enters, choose one that hasn't been chosen this turn —
• Put a +1/+1 counter on this creature.
• Create a tapped Treasure token.
• You gain 2 life.

Arboreal Alliance

When this enchantment enters, create an X/X green Treefolk creature token.
Whenever you attack with one or more Elves, populate. (Create a token that's a copy of a creature token you control.)

Rumor Gatherer

Alliance — Whenever another creature you control enters, scry 1. If this is the second time this ability has resolved this turn, draw a card instead.