Raging River

Whenever one or more creatures you control attack, each defending player divides all creatures without flying they control into a "left" pile and a "right" pile. Then, for each attacking creature you control, choose "left" or "right." That creature can't be blocked this combat except by creatures with flying and creatures in a pile with the chosen label.

Confusion in the Ranks

Whenever an artifact, creature, or enchantment enters, its controller chooses target permanent another player controls that shares a card type with it. Exchange control of those permanents.

Season of the Witch

At the beginning of your upkeep, sacrifice Season of the Witch unless you pay 2 life.
At the beginning of the end step, destroy all untapped creatures that didn't attack this turn, except for creatures that couldn't attack.

Sonic Seizure

As an additional cost to cast this spell, discard a card at random.
Sonic Seizure deals 3 damage to any target.

Crystalline Giant

At the beginning of combat on your turn, choose a kind of counter at random that Crystalline Giant doesn't have on it from among flying, first strike, deathtouch, hexproof, lifelink, menace, reach, trample, vigilance, and +1/+1. Put a counter of that kind on Crystalline Giant.

Last One Standing

Choose a creature at random, then destroy the rest.

Silent Arbiter

No more than one creature can attack each combat.
No more than one creature can block each combat.

Goblin Game

Each player hides at least one item, then all players reveal them simultaneously. Each player loses life equal to the number of items they revealed. The player who revealed the fewest items then loses half their life, rounded up. If two or more players are tied for fewest, each loses half their life, rounded up.

Cult of Skaro

Whenever Cult of Skaro attacks, choose one at random —
• Thay — Put a +1/+1 counter on each artifact creature you control.
• Caan — Draw two cards.
• Sec — Create a 3/3 black Dalek artifact creature token with menace.
• Jast — Each opponent loses 4 life.

Search for Survivors

Reorder your graveyard at random. An opponent chooses a card at random in your graveyard. If it's a creature card, put it onto the battlefield. Otherwise, exile it.

Illicit Auction

Each player may bid life for control of target creature. You start the bidding with a bid of 0. In turn order, each player may top the high bid. The bidding ends if the high bid stands. The high bidder loses life equal to the high bid and gains control of the creature. (This effect lasts indefinitely.)

Wildfire Devils

When Wildfire Devils enters and at the beginning of your upkeep, choose a player at random. That player exiles an instant or sorcery card from their graveyard. Copy that card. You may cast the copy without paying its mana cost.

Wild Research

{1}{W}: Search your library for an enchantment card and reveal that card. Put it into your hand, then discard a card at random. Then shuffle.
{1}{U}: Search your library for an instant card and reveal that card. Put it into your hand, then discard a card at random. Then shuffle.

Grip of Chaos

Whenever a spell or ability is put onto the stack, if it has a single target, reselect its target at random. (Select from among all legal targets.)

Pain's Reward

Each player may bid life. You start the bidding with a bid of any number. In turn order, each player may top the high bid. The bidding ends if the high bid stands. The high bidder loses life equal to the high bid and draws four cards.

Timesifter

At the beginning of each upkeep, each player exiles the top card of their library. The player who exiled the card with the highest mana value takes an extra turn after this one. If two or more players' cards are tied for highest, the tied players repeat this process until the tie is broken.

Six-Sided Die

Choose target creature. Roll a six-sided die.
1 — It has base toughness 1 until end of turn.
2 — Put two -1/-1 counters on it.
3 — Six-Sided Die deals 3 damage to it and you gain 3 life.
4 — It gets -4/-4 until end of turn.
5 — Destroy it.
6 — Exile it.

Scrambleverse

For each nonland permanent, choose a player at random. Then each player gains control of each permanent for which they were chosen. Untap those permanents.