34 cards where the text includes “{t}: add {u}” and the card types include “artifact”

Chronatog Totem (Time Spiral #252)
Dimir Cluestone (Dragon's Maze #138)
Dimir Keyrune (Commander Legends: Battle for Baldur's Gate #856)
Dimir Locket (Zendikar Rising Commander #111)
Dimir Signet (Ravnica: Clue Edition #221)
Drake-Skull Cameo (Invasion #302)
Eye of Ramos (Mercadian Masques #294)
Five Hundred Year Diary (Doctor Who #42)
Forger's Foundry (Outlaws of Thunder Junction Commander #14)
Izzet Cluestone (Dragon's Maze #141)
Izzet Keyrune (Return to Ravnica #230)
Izzet Locket (Commander 2019 #215)
Izzet Signet (Outlaws of Thunder Junction Commander #259)
Jeskai Banner (Khans of Tarkir #222)
Lapis Orb of Dragonkind (Commander Legends: Battle for Baldur's Gate #82)
Machine God's Effigy (The Brothers' War Commander #16)
Midnight Clock (Outlaws of Thunder Junction Commander #100)
Misleading Signpost (Wilds of Eldraine Commander #11)
Mistvault Bridge (Modern Horizons 2 #249)
Mistvein Borderpost (Archenemy #90)
Mox Sapphire (Vintage Masters #9)
Nardole, Resourceful Cyborg (Doctor Who #50)
Oaken Siren (The Lost Caverns of Ixalan #66)
Obelisk of Grixis (Archenemy: Nicol Bolas #88)
Raugrin Crystal (Ikoria: Lair of Behemoths #238)
Seat of the Synod (Commander 2018 #278)
Silumgar Monument (Dragons of Tarkir #243)
Silverbluff Bridge (Modern Horizons 2 #255)
Silver Myr (Neon Dynasty Commander #158)
Sky Diamond (Commander Legends: Battle for Baldur's Gate #337)
Talisman of Creativity (Commander Masters #979)
Talisman of Dominance (Murders at Karlov Manor Commander #242)
The Everflowing Well // The Myriad Pools (The Lost Caverns of Ixalan #56)
The Everflowing Well // The Myriad Pools (The Lost Caverns of Ixalan #56)
Visage of Bolas (Hour of Devastation #208)

This search is finished. Now the real work can begin.