mtg garth one eye cards One-Eye | Deadeye Navigator You may cast the copy Garth One-Eye | Modern Horizons

The Tabernacle at Pendrell Vale is also pretty broken as a land that can wrath away your opponent's board or at least heavily tax your opponent's mana each turn

Most of these are also legendary, so they make excellent commanders as well

Still, it meets our criteria, even if the artifact half is lacking

(2025-06-06) If you cast a spell "without paying its mana cost," you can't choose to cast it for any alternative costs

His activated ability, however, is perhaps the absolute coolest ability on this whole list

His ability lets you turn dead cards into combat strength, and this also makes him really hard to block/remove