"Any number" effects like this is pretty effective usually, and you could go a long way by stealing other players artifacts and enchantments to sacrifice to this
At just one creature, you get your normal mana rate
It will counter anything, then let you cast a free spell from your graveyard with that mana cost or fewer if they are an instant, sorcery, dork or walker of the planes
Orfeo, the Boulder Nimble Larcenist Ob Nixilis, the Adversary Obscura Ascendancy Obscura Charm Obscura Interceptor Ognis, the Dragon's Lash Park Heights Pegasus Queza, Augur of Agonies Raffine, Scheming Seer Rakish Revelers Rigo, Streetwise Mentor Riveteers Ascendancy Riveteers Charm Rocco, Cabaretti Caterer Scheming Fence Security Rhox Shattered Seraph Snooping Newsie Soul of Emancipation Spara's Adjudicators Stimulus Package Syndicate Infiltrator Tainted Indulgence Toluz, Clever Conductor Unleash the Inferno Void Rend Ziatora, the Incinerator Ziatora's Envoy ARTIFACT Arc Spitter Brass Knuckles Cement Shoes Chrome Cat Getaway Car Gilded Pinions Halo Scarab Luxior, Giada's Gift Ominous Parcel Paragon of Modernity Quick-Draw Dagger Scuttling Butler Suspicious Bookcase Unlicensed Hearse LAND Botanical Plaza Brokers Hideout Cabaretti Courtyard Jetmir's Garden Maestros Theater Obscura Storefront Racers' Ring Raffine's Tower Riveteers Overlook Skybridge Towers Spara's Headquarters Tramway Station Waterfront District Xander's Lounge Ziatora's Proving Ground Plains Plains Island Island Swamp Swamp Mountain Mountain Forest Forest WHITE | BLUE | BLACK | RED | GREEN MULTICOLORED | ARTIFACT | LAND | ALL CARDS
