Pteron Ghost

Regeneration was always a creature-protection word in the abstract, but an artifact-matters block needed a way to bend it toward the metal, and this flying body is one answer: a 1/1 that trades itself to save an artifact from destruction or lethal damage. The design reads as filler until you notice how narrow the window is. A regeneration shield only matters when something is already aimed at your artifact, and you have to pre-empt that by cracking the Ghost before the damage resolves or the Wrath lands, which means you are spending a whole creature and a card to keep one artifact around. That cost-to-payoff ratio is why the effect lives on a 1/1 with evasion rather than something splashier: the flying gives it a reason to be in the deck before the regeneration is ever relevant, so the artifact-saving clause is a contingency rather than a plan. The unflattering context is the era it came from, when indestructible was being sold as the cleaner, no-strings version of exactly this protection. A creature whose job is to shield an artifact from death reads as the worse-engineered sibling of a keyword that made the saving unnecessary in the first place.