That you can use even the turn you tap out for it
As the name suggests, these cards are the most common ones in the game

Here are some notable budget options that I've come across in my research: Creature Removal: Bone Shredder, Nekrataal, Faceless Butcher, Murderous Redcap, Siege-Gang Commander, Goblin Sharpshooter Artifact Removal: Leonin Relic-Warder, Manic Vandal Enchantment Removal: Monk Realist, War Priest of Thune, Soltari Visionary Graveyard Removal: Agent of Erebos, Withered Wretch Versatile Removal: Fiend Hunter, Duergar Hedge-Mage Hand Disruption: Sin Collector, Tidehollow Sculler, Mesmeric Fiend, Sadistic Hypnotist Anti-Stuff: Vryn Wingmare Board Wipe: Magus of the Disk, False Prophet Protection: Mother of Runes, Grand Abolisher Card Advantage / Tutor: Mentor of the Meek, Prophetic Flamespeaker, Disciple of Bolas, Bygone Bishop, Vulturous Aven, Pain Seer, Grenzo, Dungeon Warden, Relic Seeker, Weathered Wayfarer Ramp: Burnished Hart, Solemn Simulacrum, Kor Cartographer Note on Mesmeric Fiend, Fiend Hunter, Leonin Relic-Warder, and similar: these cards have a trick to permanently exile their targets

It could also be neat to have cards that cared about any form of bending
I've dreamed of what it might look like since those early days over 20 years ago, and now at long last we're here
In a 1v1 game, youll get two uses out of this compared to your opponents one, but youre still paying the to cast it