33 cards where the card types include “artifact” and the text includes “ add ” and the mana value = 4

Thran Dynamo (C19)
Hedron Archive (CLB)
Nyx Lotus (THB)
Primal Amulet // Primal Wellspring (XLN)
Primal Amulet // Primal Wellspring (XLN)
Krark-Clan Ironworks (5DN)
Firemind Vessel (2X2)
Sisay's Ring (CMR)
Empowered Autogenerator (C19)
Conqueror's Galleon // Conqueror's Foothold (XLN)
Conqueror's Galleon // Conqueror's Foothold (XLN)
Crystalline Crawler (CM2)
Golden Guardian // Gold-Forge Garrison (RIX)
Golden Guardian // Gold-Forge Garrison (RIX)
Ur-Golem's Eye (C14)
Kolvori, God of Kinship // The Ringhart Crest (KHM)
Kolvori, God of Kinship // The Ringhart Crest (KHM)
Paradise Plume (C21)
Lavabrink Floodgates (C20)
Tanuki Transplanter (NEC)
Gemstone Array (5DN)
Khalni Gem (ZEN)
Signpost Scarecrow (JMP)
Visage of Bolas (HOU)
Crossroads Candleguide (MID)
Su-Chi (VMA)
Charmed Pendant (ODY)
Ice Cauldron (ME4)
Black Mana Battery (4ED)
Diamond Kaleidoscope (VIS)
Blue Mana Battery (4ED)
Red Mana Battery (4ED)
Green Mana Battery (4ED)
White Mana Battery (4ED)
Key to the Archive (YMID)
Sarevok's Tome (CLB)
Stonespeaker Crystal (CLB)

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