Kardur, Doomscourge

When Kardur, Doomscourge enters, until your next turn, creatures your opponents control attack each combat if able and attack a player other than you if able.
Whenever an attacking creature dies, each opponent loses 1 life and you gain 1 life.

Gift of the Deity

Enchant creature
As long as enchanted creature is black, it gets +1/+1 and has deathtouch. (Any amount of damage it deals to a creature is enough to destroy that creature.)
As long as enchanted creature is green, it gets +1/+1 and all creatures able to block it do so.

Chandra's Ignition

Target creature you control deals damage equal to its power to each other creature and each opponent.

Prey Upon

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Maddening Imp

Flying
{T}: Non-Wall creatures the active player controls attack this turn if able. At the beginning of the next end step, destroy each of those creatures that didn't attack this turn. Activate only during an opponent's turn and only before combat.

Sweeping Cleave

Target creature you control gains double strike until end of turn. (Then exile this card. You may cast the artifact later from exile.)

Two-Handed Axe

Whenever equipped creature attacks, double its power until end of turn.
Equip {1}{R}

Two-Handed Axe // Sweeping Cleave

Prizefight

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)
Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Neyith of the Dire Hunt

Whenever one or more creatures you control fight or become blocked, draw a card.
At the beginning of combat on your turn, you may pay {2}{R/G}. If you do, double target creature's power until end of turn. That creature must be blocked this combat if able. ({R/G} can be paid with either {R} or {G}.)

Mr. Orfeo, the Boulder

Whenever you attack, double target creature's power until end of turn.

Boxing Ring

Whenever a creature you control enters, it fights up to one target creature you don't control with the same mana value.
{T}: Create a Treasure token. Activate only if you control a creature that fought this turn.

Ulvenwald Tracker

{1}{G}, {T}: Target creature you control fights another target creature.

Ignoble Hierarch

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{T}: Add {B}, {R}, or {G}.

Maarika, Brutal Gladiator

Maarika, Brutal Gladiator must be blocked if able.
As long as it's your turn, Maarika has indestructible.
Whenever Maarika deals damage to a creature, if that creature was dealt excess damage this turn, that creature's controller sacrifices a noncreature, nonland permanent.

Ancient Animus

Put a +1/+1 counter on target creature you control if it's legendary. Then it fights target creature an opponent controls. (Each deals damage equal to its power to the other.)

Basilisk Collar

Equipped creature has deathtouch and lifelink. (Any amount of damage it deals to a creature is enough to destroy it. Damage dealt by this creature also causes you to gain that much life.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)