{G}, Discard a card: Crashing Centaur gains trample until end of turn. Threshold — As long as seven or more cards are in your graveyard, Crashing Centaur gets +2/+2 and has shroud.
Equipped creature has "{T}: This creature deals 1 damage to target player or planeswalker. Roll a six-sided die. On a 5 or higher, untap it." Equip {2}
"Time for you to meet the brains of this operation!" —The Big Idea
Enchant player Whenever enchanted player casts a noncreature spell, roll a d6. Maddening Hex deals damage to that player equal to the result. Then attach Maddening Hex to another one of your opponents chosen at random.
Whenever Rakshasa Debaser attacks, put target creature card from defending player's graveyard onto the battlefield under your control. Encore {6}{B}{B}
Target player reveals their hand. You choose a Spirit or Arcane card from it. That player discards that card.
"The wizards of Takenuma Swamp faced the horrors of humanity every day. It's no wonder they fared so well against the kami." —Observations of the Kami War
{1}{U}, {T}: Untap target artifact an opponent controls and gain control of it until end of turn. It gains haste until end of turn. When you lose control of the artifact, tap it.
Create an X/X blue and red Weird creature token, where X is the number of instant and sorcery cards in your graveyard. Then you may return an instant or sorcery card from your graveyard to your hand. Exile Experimental Overload.
Explosions aren't necessarily failures, just a different kind of success.
Flying Unearthly Power — Instant and sorcery spells you cast cost {1} less to cast for each creature token you control. Blade of Magnus — Whenever Magnus the Red deals combat damage to a player, create a 3/3 red Spawn creature token.
Deathtouch When Skullwinder enters the battlefield, return target card from your graveyard to your hand, then choose an opponent. That player returns a card from their graveyard to their hand.
Bestow {3}{U}{U} When Crystalline Nautilus becomes the target of a spell or ability, sacrifice it. Enchanted creature gets +4/+4 and has "When this creature becomes the target of a spell or ability, sacrifice it."
Look at the top three cards of your library. You may put those cards on the bottom of your library in any order. If you do, return Petals of Insight to its owner's hand. Otherwise, draw three cards.