Sarevok, Deathbringer

At the beginning of each player's end step, if no permanents left the battlefield this turn, that player loses X life, where X is Sarevok's power.
Choose a Background (You can have a Background as a second commander.)

Odric's Outrider

Whenever this creature or another creature you control dies, put a +1/+1 counter on target creature you control.

Orzhov Signet

Serene Steward

Whenever you gain life, you may pay {W}. If you do, put a +1/+1 counter on target creature.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice this artifact: Draw a card.

Painful Truths

Converge — You draw X cards and you lose X life, where X is the number of colors of mana spent to cast this spell.

Luminous Phantom

Flying
Whenever another creature you control leaves the battlefield, you gain 1 life.
If Luminous Phantom would be put into a graveyard from anywhere, exile it instead.

Lunarch Veteran

Whenever another creature you control enters, you gain 1 life.
Disturb {1}{W} (You may cast this card from your graveyard transformed for its disturb cost.)

Lunarch Veteran // Luminous Phantom

Swamp

Temple of Aclazotz

(Transforms from Arguel's Blood Fast.)
{T}: Add {B}.
{T}, Sacrifice a creature: You gain life equal to the sacrificed creature's toughness.

Arguel's Blood Fast

{1}{B}, Pay 2 life: Draw a card.
At the beginning of your upkeep, if you have 5 or less life, you may transform Arguel's Blood Fast.

Arguel's Blood Fast // Temple of Aclazotz

Keen-Eyed Raven

Flying (This creature can't be blocked except by creatures with flying or reach.)
When this creature enters, put a +1/+1 counter on another target creature you control.

Elas il-Kor, Sadistic Pilgrim

Deathtouch
Whenever another creature you control enters, you gain 1 life.
Whenever another creature you control dies, each opponent loses 1 life.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Eye of Vecna

When Eye of Vecna enters, you draw a card and you lose 2 life.
At the beginning of your upkeep, you may pay {2}. If you do, you draw a card and you lose 2 life.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Seedpod Caretaker

When this creature enters, choose one —
• Put a +1/+1 counter on target artifact or creature you control.
• Transform target Incubator token you control.

Charcoal Diamond

This artifact enters tapped.
{T}: Add {B}.

Ollenbock Escort

Vigilance
Sacrifice this creature: Target creature you control with a +1/+1 counter on it gains lifelink and indestructible until end of turn.

Damnable Pact

Target player draws X cards and loses X life.

Star Pupil

This creature enters with a +1/+1 counter on it.
When this creature dies, put its counters on target creature you control.

Steel Dromedary

This creature enters tapped with two +1/+1 counters on it.
This creature doesn't untap during your untap step if it has a +1/+1 counter on it.
At the beginning of combat on your turn, you may move a +1/+1 counter from this creature onto target creature.

Union of the Third Path

Draw a card, then you gain life equal to the number of cards in your hand.

Far Traveler

Commander creatures you own have "At the beginning of your end step, exile up to one target tapped creature you control, then return it to the battlefield under its owner's control."

Ironpaw Aspirant

When this creature enters, put a +1/+1 counter on target creature.

Light of Hope

Choose one —
• You gain 4 life.
• Destroy target enchantment.
• Put a +1/+1 counter on target creature.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Fellwar Stone

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

Blackblade Reforged

Equipped creature gets +1/+1 for each land you control.
Equip legendary creature {3}
Equip {7}

Feat of Resistance

Put a +1/+1 counter on target creature you control. It gains protection from the color of your choice until end of turn. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything of that color.)

Luminarch Aspirant

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control.

Blood Scrivener

If you would draw a card while you have no cards in hand, instead you draw two cards and you lose 1 life.

Arcane Signet

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

Sol Ring

Backup Agent

Take Up the Shield

Put a +1/+1 counter on target creature. It gains lifelink and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Call of the Ring

At the beginning of your upkeep, the Ring tempts you.
Whenever you choose a creature as your Ring-bearer, you may pay 2 life. If you do, draw a card.

Command the Dreadhorde

Choose any number of target creature and/or planeswalker cards in graveyards. Command the Dreadhorde deals damage to you equal to the total mana value of those cards. Put them onto the battlefield under your control.

Iron Bully

Menace (This creature can't be blocked except by two or more creatures.)
When this creature enters, put a +1/+1 counter on target creature.

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.

Sign in Blood

Target player draws two cards and loses 2 life.

Blood Pact

Rush of Vitality

Target creature gets +1/+0 and gains lifelink and indestructible until end of turn. (Damage dealt by that creature also causes its controller to gain that much life, and it can't be destroyed by damage or effects that say "destroy.")

Teyo's Lightshield

When this creature enters, put a +1/+1 counter on target creature you control.

Oblivion's Hunger

Target creature you control gains indestructible until end of turn. Draw a card if that creature has a +1/+1 counter on it. (Damage and effects that say "destroy" don't destroy the creature.)

Marble Diamond

This artifact enters tapped.
{T}: Add {W}.

Armillary Sphere

{2}, {T}, Sacrifice this artifact: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

Idyllic Grange

({T}: Add {W}.)
This land enters tapped unless you control three or more other Plains.
When this land enters untapped, put a +1/+1 counter on target creature you control.

Cradle of Vitality

Whenever you gain life, you may pay {1}{W}. If you do, put a +1/+1 counter on target creature for each 1 life you gained.

Plains

Cleric Class

(Gain the next level as a sorcery to add its ability.)
If you would gain life, you gain that much life plus 1 instead.
{3}{W}: Level 2
Whenever you gain life, put a +1/+1 counter on target creature you control.
{4}{W}: Level 3
When this Class becomes level 3, return target creature card from your graveyard to the battlefield. You gain life equal to that creature's toughness.