Codie, Vociferous Codex

You can't cast permanent spells.
{4}, {T}: Add {W}{U}{B}{R}{G}. When you next cast a spell this turn, exile cards from the top of your library until you exile an instant or sorcery card with lesser mana value. Until end of turn, you may cast that card without paying its mana cost. Put each other card exiled this way on the bottom of your library in a random order.

Time Stretch

Target player takes two extra turns after this one.

Chant of Vitu-Ghazi

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Prevent all damage that would be dealt by creatures this turn. You gain life equal to the damage prevented this way.

Emergency Powers

Each player shuffles their hand and graveyard into their library, then draws seven cards. Exile Emergency Powers.
Addendum — If you cast this spell during your main phase, you may put a permanent card with mana value 7 or less from your hand onto the battlefield.

Extract from Darkness

Each player mills two cards. Then you put a creature card from a graveyard onto the battlefield under your control.

Quick Study

Duneblast

Choose up to one creature. Destroy the rest.

Slave of Bolas

Gain control of target creature. Untap that creature. It gains haste until end of turn. Sacrifice it at the beginning of the next end step.

Ruinous Ultimatum

Destroy all nonland permanents your opponents control.

Emergent Ultimatum

Search your library for up to three monocolored cards with different names and exile them. An opponent chooses one of those cards. Shuffle that card into your library. You may cast the other cards without paying their mana costs. Exile Emergent Ultimatum.

Farewell

Choose one or more —
• Exile all artifacts.
• Exile all creatures.
• Exile all enchantments.
• Exile all graveyards.

Culling Ritual

Destroy each nonland permanent with mana value 2 or less. Add {B} or {G} for each permanent destroyed this way.

Inspired Ultimatum

Target player gains 5 life, Inspired Ultimatum deals 5 damage to any target, then you draw five cards.

Maestros Confluence

Choose three. You may choose the same mode more than once.
• Return target monocolored instant or sorcery card from your graveyard to your hand.
• Target creature gets -3/-3 until end of turn.
• Goad each creature target player controls. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Rise of the Dark Realms

Put all creature cards from all graveyards onto the battlefield under your control.

Treasure Cruise

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Draw three cards.

Dig Through Time

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Look at the top seven cards of your library. Put two of them into your hand and the rest on the bottom of your library in any order.

Rowdy Research

This spell costs {1} less to cast for each creature that attacked this turn.
Draw three cards.

Blood for the Blood God!

This spell costs {1} less to cast for each creature that died this turn.
Discard your hand, then draw eight cards. Blood for the Blood God! deals 8 damage to each opponent. Exile Blood for the Blood God!