Fall of the Impostor

Two chapters of setup for one chapter of removal, and the setup is the tax that lets Selesnya touch an effect its identity usually skirts. The final chapter's exile is unusually clean for the color pair: no creature-type restriction, no life-swing rider, no way for the opponent to redirect it once the trigger resolves. What it is not is unconditional. It always takes the creature with the greatest power among the targeted opponent's board, which means it cannot dig past a large threat to answer the small utility creature actually causing you problems; a mana dork or an evasive one-drop can sit safely under a beater the spell is compelled to take instead. Green and white pay for that clean exile in two ways: it can only reach the biggest body, and it lands only after two of their own turns have passed. A Saga adds its lore counter as it enters and after your draw step, so the removal is telegraphed the moment the enchantment resolves, and a savvy opponent can hold back their bomb and feed a disposable creature to chapter III. The two +1/+1 counters in chapters I and II are the wrinkle that keeps the delay from being dead time. Because those chapters can target any creature, they double as a lever on the exile itself: pile the counters onto an opponent's small utility creature to inflate its power past their natural largest threat, and chapter III is forced to take the one you actually wanted gone.