Oni of Wild Places

Haste
At the beginning of your upkeep, return a red creature you control to its owner's hand.

Rakdos, Lord of Riots

You can't cast this spell unless an opponent lost life this turn.
Flying, trample
Creature spells you cast cost {1} less to cast for each 1 life your opponents have lost this turn.

Heartless Hidetsugu

{T}: Heartless Hidetsugu deals damage to each player equal to half that player's life total, rounded down.

Indulgent Tormentor

Flying
At the beginning of your upkeep, draw a card unless target opponent sacrifices a creature or pays 3 life.

Sokenzan Bruiser

Mountainwalk (This creature can't be blocked as long as defending player controls a Mountain.)

Blade of the Oni

Menace
Equipped creature has base power and toughness 5/5, has menace, and is a black Demon in addition to its other colors and types.
Reconfigure {2}{B}{B} ({2}{B}{B}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Ogre-Head Helm

Equipped creature gets +2/+2.
Whenever Ogre-Head Helm or equipped creature deals combat damage to a player, you may sacrifice it. If you do, discard your hand, then draw three cards.
Reconfigure {3} ({3}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Master of Cruelties

First strike, deathtouch
Master of Cruelties can only attack alone.
Whenever Master of Cruelties attacks a player and isn't blocked, that player's life total becomes 1. Master of Cruelties assigns no combat damage this combat.

Defiler of Souls

Flying
At the beginning of each player's upkeep, that player sacrifices a monocolored creature.

Poisonbelly Ogre

Whenever another creature enters the battlefield, its controller loses 1 life.

Ogre Marauder

Whenever Ogre Marauder attacks, it gains "Ogre Marauder can't be blocked" until end of turn unless defending player sacrifices a creature.

Razorjaw Oni

Goremand

As an additional cost to cast this spell, sacrifice a creature.
Flying
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
When Goremand enters the battlefield, each opponent sacrifices a creature.

Deathcurse Ogre

When Deathcurse Ogre dies, each player loses 3 life.

Skull Collector

At the beginning of your upkeep, return a black creature you control to its owner's hand.
{1}{B}: Regenerate Skull Collector.

Turret Ogre

Reach (This creature can block creatures with flying.)
When Turret Ogre enters the battlefield, if you control another creature with power 4 or greater, Turret Ogre deals 2 damage to each opponent.

Hidetsugu, Devouring Chaos

{B}, Sacrifice a creature: Scry 2.
{2}{R}, {T}: Exile the top card of your library. You may play that card this turn. When you exile a nonland card this way, Hidetsugu, Devouring Chaos deals damage equal to the exiled card's mana value to any target.

Dreadhound

When Dreadhound enters the battlefield, mill three cards. (Put the top three cards of your library into your graveyard.)
Whenever a creature dies or a creature card is put into a graveyard from a library, each opponent loses 1 life.

Bloodthirsty Ogre

{T}: Put a devotion counter on Bloodthirsty Ogre.
{T}: Target creature gets -X/-X until end of turn, where X is the number of devotion counters on Bloodthirsty Ogre. Activate only if you control a Demon.

Rakdos Roustabout

Whenever Rakdos Roustabout becomes blocked, it deals 1 damage to the player or planeswalker it's attacking.

Vessel of the All-Consuming

Trample
Whenever Vessel of the All-Consuming deals damage, put a +1/+1 counter on it.
Whenever Vessel of the All-Consuming deals damage to a player, if it has dealt 10 or more damage to that player this turn, they lose the game.

Hidetsugu Consumes All

(As this Saga enters and after your draw step, add a lore counter.)
I — Destroy each nonland permanent with mana value 1 or less.
II — Exile all graveyards.
III — Exile this Saga, then return it to the battlefield transformed under your control.

Hidetsugu Consumes All // Vessel of the All-Consuming

Gutwrencher Oni

Trample
At the beginning of your upkeep, discard a card if you don't control an Ogre.

Kazuul, Tyrant of the Cliffs

Whenever a creature an opponent controls attacks, if you're the defending player, create a 3/3 red Ogre creature token unless that creature's controller pays {3}.

Withengar Unbound

Flying, intimidate, trample (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a player loses the game, put thirteen +1/+1 counters on Withengar Unbound.

Elbrus, the Binding Blade

Equipped creature gets +1/+0.
When equipped creature deals combat damage to a player, unattach Elbrus, the Binding Blade, then transform it.
Equip {1}

Elbrus, the Binding Blade // Withengar Unbound

Singe-Mind Ogre

When Singe-Mind Ogre enters the battlefield, target player reveals a card at random from their hand, then loses life equal to that card's mana value.

Rune-Scarred Demon

Flying
When Rune-Scarred Demon enters the battlefield, search your library for a card, put it into your hand, then shuffle.

Storm Caller

When Storm Caller enters the battlefield, it deals 2 damage to each opponent.

Desecration Demon

Flying
At the beginning of each combat, any opponent may sacrifice a creature. If a player does, tap Desecration Demon and put a +1/+1 counter on it.

Mausoleum Turnkey

When Mausoleum Turnkey enters the battlefield, return target creature card of an opponent's choice from your graveyard to your hand.

Demon of Loathing

Flying, trample
Whenever Demon of Loathing deals combat damage to a player, that player sacrifices a creature.

Ogre Siegebreaker

{2}{B}{R}: Destroy target creature that was dealt damage this turn.

Painwracker Oni

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
At the beginning of your upkeep, sacrifice a creature if you don't control an Ogre.

Ogre Menial

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{R}: Ogre Menial gets +1/+0 until end of turn.

Scourge of Numai

At the beginning of your upkeep, you lose 2 life if you don't control an Ogre.

Villainous Ogre

Villainous Ogre can't block.
As long as you control a Demon, Villainous Ogre has "{B}: Regenerate Villainous Ogre."

Undercity Scavenger

When Undercity Scavenger enters the battlefield, you may sacrifice another creature. If you do, put two +1/+1 counters on Undercity Scavenger, then scry 2.

Takenuma Bleeder

Whenever Takenuma Bleeder attacks or blocks, you lose 1 life if you don't control a Demon.

Kazuul's Toll Collector

{0}: Attach target Equipment you control to Kazuul's Toll Collector. Activate only as a sorcery.

Ogre Arsonist

When Ogre Arsonist enters the battlefield, destroy target land.

Herald of Anguish

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Flying
At the beginning of your end step, each opponent discards a card.
{1}{B}, Sacrifice an artifact: Target creature gets -2/-2 until end of turn.

Goka the Unjust

{T}: Goka the Unjust deals 4 damage to target creature that was dealt damage this turn.

Initiate of Blood

{T}: Initiate of Blood deals 1 damage to target creature that was dealt damage this turn. When that creature dies this turn, flip Initiate of Blood.

Initiate of Blood // Goka the Unjust

Doom Whisperer

Flying, trample
Pay 2 life: Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Blood Speaker

At the beginning of your upkeep, you may sacrifice Blood Speaker. If you do, search your library for a Demon card, reveal that card, put it into your hand, then shuffle.
Whenever a Demon enters the battlefield under your control, return Blood Speaker from your graveyard to your hand.

Raving Oni-Slave

When Raving Oni-Slave enters or leaves the battlefield, you lose 3 life if you don't control a Demon.

Kuon's Essence

At the beginning of each player's upkeep, that player sacrifices a creature.

Kuon, Ogre Ascendant

At the beginning of the end step, if three or more creatures died this turn, flip Kuon, Ogre Ascendant.

Kuon, Ogre Ascendant // Kuon's Essence

Mardu Blazebringer

When Mardu Blazebringer attacks or blocks, sacrifice it at end of combat.

Brawl-Bash Ogre

Menace (This creature can't be blocked except by two or more creatures.)
Whenever Brawl-Bash Ogre attacks, you may sacrifice another creature. If you do, Brawl-Bash Ogre gets +2/+2 until end of turn.

Griselbrand

Flying, lifelink
Pay 7 life: Draw seven cards.

Hoarding Ogre

Whenever Hoarding Ogre attacks, roll a d20.
1—9 | Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
10—19 | Create two Treasure tokens.
20 | Create three Treasure tokens.

Seizan, Perverter of Truth

At the beginning of each player's upkeep, that player loses 2 life and draws two cards.