Garrison Excavator

Menace (This creature can't be blocked except by two or more creatures.)
Whenever one or more cards leave your graveyard, create a 2/2 red and white Spirit creature token.

Hardened Academic

Flying, haste
Discard a card: This creature gains lifelink until end of turn.
Whenever one or more cards leave your graveyard, put a +1/+1 counter on target creature you control.

Spirit Mascot

Whenever one or more cards leave your graveyard, put a +1/+1 counter on this creature.

Naga Fleshcrafter

You may have this creature enter as a copy of any creature on the battlefield.
Renew — {2}{U}, Exile this card from your graveyard: Put a +1/+1 counter on target nonlegendary creature you control. Each other creature you control becomes a copy of that creature until end of turn. Activate only as a sorcery.

Dredger's Insight

Whenever one or more artifact and/or creature cards leave your graveyard, you gain 1 life.
When this enchantment enters, mill four cards. You may put an artifact, creature, or land card from among the milled cards into your hand. (To mill four cards, put the top four cards of your library into your graveyard.)

Pack a Punch

Mill a card. Put two +1/+1 counters on target creature. It gains trample until end of turn.

Kirol, History Buff

Whenever one or more cards leave your graveyard, Kirol becomes prepared. (While it's prepared, you may cast a copy of its spell. Doing so unprepares it.)

Kirol, History Buff // Pack a Punch

Icetill Explorer

You may play an additional land on each of your turns.
You may play lands from your graveyard.
Landfall — Whenever a land you control enters, mill a card.

Insidious Roots

Creature tokens you control have "{T}: Add one mana of any color."
Whenever one or more creature cards leave your graveyard, create a 0/1 green Plant creature token, then put a +1/+1 counter on each Plant you control.