Have

Starseer Mentor

Flying, vigilance
At the beginning of your end step, if you gained or lost life this turn, target opponent loses 3 life unless they sacrifice a nonland permanent of their choice or discard a card.

Starscape Cleric

Offspring {2}{B} (You may pay an additional {2}{B} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Flying
This creature can't block.
Whenever you gain life, each opponent loses 1 life.

Essence Channeler

As long as you've lost life this turn, this creature has flying and vigilance.
Whenever you gain life, put a +1/+1 counter on this creature.
When this creature dies, put its counters on target creature you control.

Scoured Barrens

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {W} or {B}.

Hazel's Nocturne

Return up to two target creature cards from your graveyard to your hand. Each opponent loses 2 life and you gain 2 life.

Plains

Ruin-Lurker Bat

Flying, lifelink
At the beginning of your end step, if you descended this turn, scry 1. (You descended if a permanent card was put into your graveyard from anywhere.)

Stargaze

Look at twice X cards from the top of your library. Put X cards from among them into your hand and the rest into your graveyard. You lose X life.

Zoraline, Cosmos Caller

Flying, vigilance
Whenever a Bat you control attacks, you gain 1 life.
Whenever Zoraline enters or attacks, you may pay {W}{B} and 2 life. When you do, return target nonland permanent card with mana value 3 or less from your graveyard to the battlefield with a finality counter on it.

Lifecreed Duo

Flying
Whenever another creature you control enters, you gain 1 life.

Sinister Monolith

At the beginning of combat on your turn, each opponent loses 1 life and you gain 1 life.
{T}, Pay 2 life, Sacrifice this artifact: Draw two cards. Activate only as a sorcery.

Banishing Light

When this enchantment enters, exile target nonland permanent an opponent controls until this enchantment leaves the battlefield.

Fell

Patchwork Banner

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{T}: Add one mana of any color.

Savor

Target creature gets -2/-2 until end of turn. Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")

Swamp

Authority of the Consuls

Creatures your opponents control enter tapped.
Whenever a creature an opponent controls enters, you gain 1 life.

Lunar Convocation

At the beginning of your end step, if you gained life this turn, each opponent loses 1 life.
At the beginning of your end step, if you gained and lost life this turn, create a 1/1 black Bat creature token with flying.
{1}{B}, Pay 2 life: Draw a card.

Mudflat Village

{T}: Add {C}.
{T}: Add {B}. Spend this mana only to cast a creature spell.
{1}{B}, {T}, Sacrifice this land: Return target Bat, Lizard, Rat, or Squirrel card from your graveyard to your hand.

Sonar Strike

Sonar Strike deals 4 damage to target attacking, blocking, or tapped creature. You gain 3 life if you control a Bat.

Starfall Invocation

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Destroy all creatures. If the gift was promised, return a creature card put into your graveyard this way to the battlefield under your control.

Deep-Cavern Bat

Flying, lifelink
When this creature enters, look at target opponent's hand. You may exile a nonland card from it until this creature leaves the battlefield.

Moonstone Harbinger

Flying, deathtouch
Whenever you gain or lose life during your turn, Bats you control get +1/+0 and gain deathtouch until end of turn. This ability triggers only once each turn.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Wax-Wane Witness

Flying, vigilance
Whenever you gain or lose life during your turn, this creature gets +1/+0 until end of turn.

Lupinflower Village

{T}: Add {C}.
{T}: Add {W}. Spend this mana only to cast a creature spell.
{1}{W}, {T}, Sacrifice this land: Look at the top six cards of your library. You may reveal a Bat, Bird, Mouse, or Rabbit card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Temple of the Dead

(Transforms from Aclazotz, Deepest Betrayal.)
{T}: Add {B}.
{2}{B}, {T}: Transform this land. Activate only if a player has one or fewer cards in hand and only as a sorcery.

Aclazotz, Deepest Betrayal

Flying, lifelink
Whenever Aclazotz attacks, each opponent discards a card. For each opponent who can't, you draw a card.
Whenever an opponent discards a land card, create a 1/1 black Bat creature token with flying.
When Aclazotz dies, return it to the battlefield tapped and transformed under its owner's control.