And did I mention they are expensive
Once per turn, when a card or effect is activated (Quick Effect): You can negate the activation, and if you do, destroy it

Decklist: Praetors in Commander Jin-Gitaxias, Core Augur | Illustration by Eric Deschamps Commander (1) Planeswalker (1) Creatures (28) Benthic Biomancer Mother of Runes Spore Frog Biomancer's Familiar Ilysian Caryatid Incubation Druid Lotus Cobra Sakura-Tribe Elder Springbloom Druid Vial Smasher the Fierce Gix, Yawgmoth's Praetor Sheoldred, the Apocalypse Solemn Simulacrum Seedborn Muse Elesh Norn, Mother of Machines Urabrask, Heretic Praetor Urabrask the Hidden Vorinclex, Monstrous Raider Elesh Norn, Grand Cenobite Jin-Gitaxias, Progress Tyrant Sheoldred, Whispering One Vorinclex, Voice of Hunger Jin-Gitaxias, Core Augur Elesh Norn Jin-Gitaxias Vorinclex Sheoldred Urabrask Instants (6) Swords to Plowshares Vampiric Tutor Beast Within Unwind Akroma's Will Cosmic Intervention Sorceries (10) Demonic Tutor Bala Ged Recovery Cultivate Idyllic Tutor Kodama's Reach Migration Path Merciless Eviction Mob Rule Eerie Ultimatum Genesis Ultimatum Enchantments (8) Training Grounds Sylvan Library Ascent of the Worthy Garruk's Uprising Bear Umbra Fires of Invention Wilderness Reclamation Mana Reflection Artifacts (8) Glaring Spotlight Sol Ring Arcane Signet Fellwar Stone Illusionist's Bracers Chromatic Lantern Heartstone Lithoform Engine Lands (38) Bloodstained Mire Branchloft Pathway Brightclimb Pathway Command Tower Cragcrown Pathway Fabled Passage Flooded Strand Forbidden Orchard Forest x4 Hallowed Fountain Indatha Triome Island x2 Ketria Triome Mountain x3 Plains x2 Raugrin Triome Riverglide Pathway Sacred Foundry Savai Triome Spectator Seating Stomping Ground Swamp x2 Temple Garden Temple of Mystery The World Tree Undergrowth Stadium Watery Grave Windswept Heath Wooded Foothills Zagoth Triome All together the Praetors only make up a small portion of unique cards in a deck and dont have much synergy with other cards in Magic

A "square-cut Base Set Charizard" listed for $200 is not a bargain
Are you interested in learning more about rare Magic: The Gathering cards
This is hard to cast and hard to abuse, so I don't think it even deserves a build around grade