Codie, Vociferous Codex + High Alert + Agatha of the Vile Cauldron

Codie, Vociferous Codex

High Alert

Agatha of the Vile Cauldron

How it works

1. Activate Codie by paying 1 and tapping it, adding .
2. Activate High Alert by paying 2, untapping Codie.
3. Repeat as desired, skipping step 2 on the final iteration.
4. Once you have an arbitrarily large number of Codie triggers, cast any spell by paying its mana cost, reduced by the added in step 1.
5. Codie triggers for each time you activated its ability.
6. Resolve the first trigger, causing you to exile cards from the top of your library until you exile an instant or sorcery spell with lesser mana value, and allowing you to cast that spell without paying its mana cost.
7. Repeat step 6 for each remaining trigger.
8. You may also repeat this combo for each instant and/or sorcery card in your hand as mana permits, and on subsequent turns.

This clever loop turns Codie, Vociferous Codex into a massive cascade engine by leaning on Agatha of the Vile Cauldron to drastically slash activation costs. While Agatha's power reduces the price of activating Codie's mana and cascade ability, High Alert steps in as the crucial untap engine that lets you repeat the process endlessly. By constantly untapping the Codex, you stockpile a towering stack of delayed cascade triggers and generate an immense surplus of colors, allowing you to flip through your entire library and cast a devastating wave of instant and sorcery spells for free.