all ultimatum cards mtg Ruinous | Ikoria: Lair of Behemoths | Modern Destroy all nonland permanents your opponents control. MTGNexus - Cruel Ultimatum

Doubling Season and Vorinclex make your deck even more nutty, and there are a whole suite of powerful counterspells and redicting effects (Mana Drain is particularly good, here) that will ensure your game plan goes off without a hitch

But when you need a board wipe, you can use the Exude Toxin omen, dropping a powerful -X/-X effect that wipes out smaller non-dragon creatures

This ability also works well with other cards incentivizing opponents to attack, such as Propaganda or Ghostly Prison

The next best things are the Tron lands

Uro, Titan of Nature's Wrath | Illustration by Vincent Proce Simic creatures in MTG have a green-blue, or Simic color identity

If your initial draw gives you The Queen, Commanding Prescene, its worth throwing everything else out to get The Queen, Regal Monarch