Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Relentless Rats

Relentless Rats gets +1/+1 for each other creature on the battlefield named Relentless Rats.
A deck can have any number of cards named Relentless Rats.

Birds of Paradise

Promise of Bunrei

When a creature you control dies, sacrifice Promise of Bunrei. If you do, create four 1/1 colorless Spirit creature tokens.

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.

Avacyn's Pilgrim

Kitchen Finks

When Kitchen Finks enters, you gain 2 life.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Strangleroot Geist

Haste
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Delighted Halfling

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a legendary spell, and that spell can't be countered.

Ashnod's Altar

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Young Wolf

Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Tayam, Luminous Enigma

Each other creature you control enters with an additional vigilance counter on it.
{3}, Remove three counters from among creatures you control: Mill three cards, then return a permanent card with mana value 3 or less from your graveyard to the battlefield.