Moderation

In Commander, Moderation fills a niche role as a group-slug piece that punishes spell-heavy decks and draw-heavy strategies simultaneously, and it earns its slot in the 31% of Zedruu the Greathearted decks that run it precisely because the donation plan turns symmetry into asymmetry. Outside Commander, the formats where Moderation is legal — Legacy, Vintage, Modern — rarely want it, since those formats are built around doing multiple powerful things per turn and any deck running Moderation is already conceding its own win condition. Knowledge Pool occupies adjacent chaos-enchantment space at a much higher price point; Moderation at bulk pricing is a cheap way to test whether the prison-enchantment angle works for your build before committing. Oathbreaker sees occasional niche use in the same Zedruu-style donate strategies that Commander popularized.