Now I have the data I need. The tournament results clearly show the picture, but let me also get the Izzet Midrange overview specifically in Standard to make sure I'm comparing correctly.
Here is the full breakdown for @Zacktrack92:
Izzet Cauldron is actually the dominant Izzet winner in Standard, but between the two decks you asked about, Izzet Lessons wins this comparison decisively. Looking at all Standard tournaments since September 2025, Izzet Lessons has won 1 tournament outright (a Standard Last Chance event) and accumulated 1,987 top 8 appearances across 2,054 total entries, with a 53% winrate (excluding draws). Izzet Midrange, by comparison, has only 1 tournament win as well but with far fewer entries at 832 and a lower 54% raw winrate. In terms of raw volume, top 8 dominance, and overall meta presence, Izzet Lessons is the much bigger deck.
Worth noting, Izzet Cauldron (a separate Izzet archetype) actually leads all Izzet variants with 15 tournament wins and 1,295 entries. If you are asking which Izzet deck is actually winning the most, Cauldron takes that crown. But head-to-head between Midrange and Lessons, Lessons is the clear answer: nearly 2.5x more entries, a higher profile in top 8 slots (8.75% meta share vs. 3.41%), and a strong 53% winrate in a wide-open field.
Sources: Data from 239 Standard tournaments (50.6% MTGO, 49.4% Melee). Recent examples: https://www.mtgo.com/decklist/standard-challenge-32-2026-03-0112834094 | https://melee.gg/Decklist/View/4ca73881-cef5-4fbe-a0bd-b40000f7abb1 | https://melee.gg/Decklist/View/68d5d967-7737-4b50-8554-b3ff00e0ec6c