Gwaihir, Greatest of the Eagles

Flying
Whenever Gwaihir attacks, target attacking creature gains flying until end of turn.
At the beginning of each end step, if you gained 3 or more life this turn, create a 3/3 white Bird creature token with flying and "Whenever this creature attacks, target attacking creature gains flying until end of turn."

Gollum, Obsessed Stalker

Skulk (This creature can't be blocked by creatures with greater power.)
At the beginning of your end step, each opponent dealt combat damage this game by a creature named Gollum, Obsessed Stalker loses life equal to the amount of life you gained this turn.

Plains

Auriok Champion

Protection from black and from red
Whenever another creature enters the battlefield, you may gain 1 life.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Sam, Loyal Attendant

Partner with Frodo, Adventurous Hobbit (When this creature enters the battlefield, target player may put Frodo into their hand from their library, then shuffle.)
At the beginning of combat on your turn, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Activated abilities of Foods you control cost {1} less to activate.

Path of Ancestry

Path of Ancestry enters the battlefield tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Ellyn Harbreeze, Busybody

{T}: Look at the top X cards of your library, where X is the number of tokens you created this turn. Put one of those cards into your hand and the rest on the bottom of your library in a random order.
Choose a Background (You can have a Background as a second commander.)

Thrull Parasite

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
{T}, Pay 2 life: Remove a counter from target nonland permanent.

Dawn of Hope

Whenever you gain life, you may pay {2}. If you do, draw a card.
{3}{W}: Create a 1/1 white Soldier creature token with lifelink.

Command Tower

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

Radiant Fountain

When Radiant Fountain enters the battlefield, you gain 2 life.
{T}: Add {C}.

Arcane Signet

Scavenging Ooze

{G}: Exile target card from a graveyard. If it was a creature card, put a +1/+1 counter on Scavenging Ooze and you gain 1 life.

Murmuring Bosk

({T}: Add {G}.)
As Murmuring Bosk enters the battlefield, you may reveal a Treefolk card from your hand. If you don't, Murmuring Bosk enters the battlefield tapped.
{T}: Add {W} or {B}. Murmuring Bosk deals 1 damage to you.

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Extraction Specialist

Lifelink
When Extraction Specialist enters the battlefield, return target creature card with mana value 2 or less from your graveyard to the battlefield. That creature can't attack or block for as long as you control Extraction Specialist.

Dina, Soul Steeper

Whenever you gain life, each opponent loses 1 life.
{1}, Sacrifice another creature: Dina, Soul Steeper gets +X/+0 until end of turn, where X is the sacrificed creature's power.

Glorious Sunrise

At the beginning of combat on your turn, choose one —
• Creatures you control get +1/+1 and gain trample until end of turn.
• Target land gains "{T}: Add {G}{G}{G}" until end of turn.
• Draw a card if you control a creature with power 3 or greater.
• You gain 3 life.

Forest

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Test of Endurance

At the beginning of your upkeep, if you have 50 or more life, you win the game.

Night's Whisper

Soul's Attendant

Whenever another creature enters the battlefield, you may gain 1 life.

Frodo, Adventurous Hobbit

Partner with Sam, Loyal Attendant
Vigilance
Whenever Frodo, Adventurous Hobbit attacks, if you gained 3 or more life this turn, the Ring tempts you. Then if Frodo is your Ring-bearer and the Ring has tempted you two or more times this game, draw a card.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Swamp

Necroblossom Snarl

As Necroblossom Snarl enters the battlefield, you may reveal a Swamp or Forest card from your hand. If you don't, Necroblossom Snarl enters the battlefield tapped.
{T}: Add {B} or {G}.

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Transguild Promenade

Transguild Promenade enters the battlefield tapped.
When Transguild Promenade enters the battlefield, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Citywide Bust

Destroy all creatures with toughness 4 or greater.

Soul Warden

Whenever another creature enters the battlefield, you gain 1 life.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Sanguine Bond

Whenever you gain life, target opponent loses that much life.

Canopy Vista

({T}: Add {G} or {W}.)
Canopy Vista enters the battlefield tapped unless you control two or more basic lands.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Essence Warden

Savvy Hunter

Whenever Savvy Hunter attacks or blocks, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Sacrifice two Foods: Draw a card.

Birds of Paradise

Huatli, the Sun's Heart

Each creature you control assigns combat damage equal to its toughness rather than its power.
−3: You gain life equal to the greatest toughness among creatures you control.

Forbidden Orchard

{T}: Add one mana of any color.
Whenever you tap Forbidden Orchard for mana, target opponent creates a 1/1 colorless Spirit creature token.

Sandsteppe Citadel

Sandsteppe Citadel enters the battlefield tapped.
{T}: Add {W}, {B}, or {G}.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Fell the Mighty

Destroy all creatures with power greater than target creature's power.

Reclamation Sage

When Reclamation Sage enters the battlefield, you may destroy target artifact or enchantment.

Don't Have

Life Insurance

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever a nontoken creature dies, you lose 1 life and create a Treasure token.

Mythos of Nethroi

Destroy target nonland permanent if it's a creature or if {G}{W} was spent to cast this spell.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Fortified Village

As Fortified Village enters the battlefield, you may reveal a Forest or Plains card from your hand. If you don't, Fortified Village enters the battlefield tapped.
{T}: Add {G} or {W}.

Woodland Cemetery

Woodland Cemetery enters the battlefield tapped unless you control a Swamp or a Forest.
{T}: Add {B} or {G}.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Trading Post

{1}, {T}, Discard a card: You gain 4 life.
{1}, {T}, Pay 1 life: Create a 0/1 white Goat creature token.
{1}, {T}, Sacrifice a creature: Return target artifact card from your graveyard to your hand.
{1}, {T}, Sacrifice an artifact: Draw a card.

Willing

Creatures you control gain deathtouch and lifelink until end of turn.
Fuse (You may cast one or both halves of this card from your hand.)

Ready

Creatures you control gain indestructible until end of turn. Untap each creature you control.
Fuse (You may cast one or both halves of this card from your hand.)

Ready // Willing

Arasta of the Endless Web

Reach
Whenever an opponent casts an instant or sorcery spell, create a 1/2 green Spider creature token with reach.

Prize Pig

Whenever you gain life, put that many ribbon counters on Prize Pig. Then if there are three or more ribbon counters on Prize Pig, remove those counters and untap it.
{T}: Add one mana of any color.

Graypelt Refuge

Graypelt Refuge enters the battlefield tapped.
When Graypelt Refuge enters the battlefield, you gain 1 life.
{T}: Add {G} or {W}.

Tithe Drinker

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Voice of the Blessed

Whenever you gain life, put a +1/+1 counter on Voice of the Blessed.
As long as Voice of the Blessed has four or more +1/+1 counters on it, it has flying and vigilance.
As long as Voice of the Blessed has ten or more +1/+1 counters on it, it has indestructible.

Serra Ascendant

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
As long as you have 30 or more life, Serra Ascendant gets +5/+5 and has flying.

Storm Herd

Create X 1/1 white Pegasus creature tokens with flying, where X is your life total.

Read the Bones

Scry 2, then draw two cards. You lose 2 life.

Khalni Garden

Khalni Garden enters the battlefield tapped.
When Khalni Garden enters the battlefield, create a 0/1 green Plant creature token.
{T}: Add {G}.

Treebeard, Gracious Host

Trample, ward {2}
When Treebeard, Gracious Host enters the battlefield, create two Food tokens.
Whenever you gain life, put that many +1/+1 counters on target Halfling or Treefolk.

Cosmos Elixir

At the beginning of your end step, draw a card if your life total is greater than your starting life total. Otherwise, you gain 2 life.

Dawn

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Return all creature cards with power 2 or less from your graveyard to your hand.

Dusk

Destroy all creatures with power 3 or greater.

Dusk // Dawn

Sol Ring

Basilica Guards

Defender
Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Abzan Charm

Choose one —
• Exile target creature with power 3 or greater.
• You draw two cards and you lose 2 life.
• Distribute two +1/+1 counters among one or two target creatures.

The Gaffer

At the beginning of each end step, if you gained 3 or more life this turn, draw a card.

Ajani, Strength of the Pride

+1: You gain life equal to the number of creatures you control plus the number of planeswalkers you control.
−2: Create a 2/2 white Cat Soldier creature token named Ajani's Pridemate with "Whenever you gain life, put a +1/+1 counter on Ajani's Pridemate."
0: If you have at least 15 life more than your starting life total, exile Ajani, Strength of the Pride and each artifact and creature your opponents control.

Well of Lost Dreams

Whenever you gain life, you may pay {X}, where X is less than or equal to the amount of life you gained. If you do, draw X cards.

Bilbo, Birthday Celebrant

If you would gain life, you gain that much life plus 1 instead.
{2}{W}{B}{G}, {T}, Exile Bilbo, Birthday Celebrant: Search your library for any number of creature cards, put them onto the battlefield, then shuffle. Activate only if you have 111 or more life.

Sunpetal Grove

Sunpetal Grove enters the battlefield tapped unless you control a Forest or a Plains.
{T}: Add {G} or {W}.

Fiendslayer Paladin

First strike (This creature deals combat damage before creatures without first strike.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Fiendslayer Paladin can't be the target of black or red spells your opponents control.

It That Rides as One

Lone Rider

First strike, lifelink
At the beginning of the end step, if you gained 3 or more life this turn, transform Lone Rider.

Lone Rider // It That Rides as One

Utter End

Pristine Talisman

Shineshadow Snarl

As Shineshadow Snarl enters the battlefield, you may reveal a Plains or Swamp card from your hand. If you don't, Shineshadow Snarl enters the battlefield tapped.
{T}: Add {W} or {B}.

Talisman of Unity

{T}: Add {C}.
{T}: Add {G} or {W}. Talisman of Unity deals 1 damage to you.

Crypt Incursion

Exile all creature cards from target player's graveyard. You gain 3 life for each card exiled this way.

Exotic Orchard

Death

Return target creature card from your graveyard to the battlefield. You lose life equal to its mana value.

Life

All lands you control become 1/1 creatures until end of turn. They're still lands.

Life // Death

Prosperous Innkeeper

When Prosperous Innkeeper enters the battlefield, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Whenever another creature enters the battlefield under your control, you gain 1 life.

Isolated Chapel

Isolated Chapel enters the battlefield tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

Trespasser's Curse

Enchant player
Whenever a creature enters the battlefield under enchanted player's control, that player loses 1 life and you gain 1 life.

Scoured Barrens

Scoured Barrens enters the battlefield tapped.
When Scoured Barrens enters the battlefield, you gain 1 life.
{T}: Add {W} or {B}.

Brushland

{T}: Add {C}.
{T}: Add {G} or {W}. Brushland deals 1 damage to you.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Krosan Verge

Krosan Verge enters the battlefield tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Krosan Verge: Search your library for a Forest card and a Plains card, put them onto the battlefield tapped, then shuffle.

Epicure of Blood

Whenever you gain life, each opponent loses 1 life.

Bishop of Rebirth

Vigilance
Whenever Bishop of Rebirth attacks, you may return target creature card with mana value 3 or less from your graveyard to the battlefield.