Ajani's Welcome

Whenever a creature you control enters, you gain 1 life.

Norin the Wary

When a player casts a spell or a creature attacks, exile Norin. Return it to the battlefield under its owner's control at the beginning of the next end step.

Wirewood Symbiote

Return an Elf you control to its owner's hand: Untap target creature. Activate only once each turn.

Tocasia's Welcome

Whenever one or more creatures you control with mana value 3 or less enter, draw a card. This ability triggers only once each turn.

Rocco, Cabaretti Caterer

When Rocco enters, if you cast it, you may search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

Saltskitter

Whenever another creature enters, exile this creature. Return this creature to the battlefield under its owner's control at the beginning of the next end step.

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.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Aura Shards

Whenever a creature you control enters, you may destroy target artifact or enchantment.

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Eternal Witness

When this creature enters, you may return target card from your graveyard to your hand.