Have

Assault Suit

Equipped creature gets +2/+2, has haste, can't attack you or planeswalkers you control, and can't be sacrificed.
At the beginning of each opponent's upkeep, you may have that player gain control of equipped creature until end of turn. If you do, untap it.
Equip {3}

Pit Fight

Target creature you control fights another target creature. (Each deals damage equal to its power to the other.)

Bushwhack

Choose one —
• Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
• Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

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.")

Garruk's Uprising

When Garruk's Uprising enters the battlefield, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (They can deal excess combat damage to the player or planeswalker they're attacking.)
Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.

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.

Ram Through

Target creature you control deals damage equal to its power to target creature you don't control. If the creature you control has trample, excess damage is dealt to that creature's controller instead.

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.

Unnatural Growth

At the beginning of each combat, double the power and toughness of each creature you control until end of turn.

Aggravated Assault

{3}{R}{R}: Untap all creatures you control. After this main phase, there is an additional combat phase followed by an additional main phase. Activate only as a sorcery.

Ulvenwald Tracker

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

Arena

{3}, {T}: Tap target creature you control and target creature of an opponent's choice they control. Those creatures fight each other. (Each deals damage equal to its power to the other.)

Surestrike Trident

Equipped creature has first strike and "{T}, Unattach Surestrike Trident: This creature deals damage equal to its power to target player or planeswalker."
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery. This card enters the battlefield unattached and stays on the battlefield if the creature leaves.)

Rancor

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When Rancor is put into a graveyard from the battlefield, return Rancor to its owner's hand.

World at War

After the first postcombat main phase this turn, there's an additional combat phase followed by an additional main phase. At the beginning of that combat, untap all creatures that attacked this turn.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Nemesis Mask

All creatures able to block equipped creature do so.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery. This card enters the battlefield unattached and stays on the battlefield if the creature leaves.)

The Grand Evolution

(As this Saga enters and after your draw step, add a lore counter.)
I — Mill ten cards. Put up to two creature cards from among the milled cards onto the battlefield.
II — Distribute seven +1/+1 counters among any number of target creatures you control.
III — Until end of turn, creatures you control gain "{1}: This creature fights target creature you don't control." Exile The Grand Evolution, then return it to the battlefield (front face up).

Vorinclex

Trample, reach
When Vorinclex enters the battlefield, search your library for up to two Forest cards, reveal them, put them into your hand, then shuffle.
{6}{G}{G}: Exile Vorinclex, then return it to the battlefield transformed under its owner's control. Activate only as a sorcery.

Vorinclex // The Grand Evolution

Eternal Thirst

Enchant creature
Enchanted creature has lifelink and "Whenever a creature an opponent controls dies, put a +1/+1 counter on this creature." (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)

Embercleave

Flash
This spell costs {1} less to cast for each attacking creature you control.
When Embercleave enters the battlefield, attach it to target creature you control.
Equipped creature gets +1/+1 and has double strike and trample.
Equip {3}

Tail Swipe

Choose target creature you control and target creature you don't control. If you cast this spell during your main phase, the creature you control gets +1/+1 until end of turn. Then those creatures fight each other. (Each deals damage equal to its power to the other.)

Curse of the Werefox

Create a Monster Role token attached to target creature you control. When you do, that creature fights up to one target creature you don't control. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has trample. Creatures that fight each deal damage equal to their power to the other.)