Guardian Beast

The rules text on this 2/4 black body is unusually load-bearing for a 1993 design, and almost every clause is doing real work. The protection is conditional on the Beast staying untapped, which turns a static shield into a tempo lever: opponents can break the lock by forcing it into combat, by tapping it down, or by killing the Beast outright, and the artifact player has to decide whether to swing with their bodyguard or hold it back. The carve-outs are the interesting part. Noncreature artifacts get indestructible, can't be enchanted, and can't be stolen, which reads like a checklist of every answer a 1993 environment had to artifacts: Shatter effects, Control Magic, the various Aura locks. Crucially, the protection sits on a black creature rather than a colorless artifact, so the Beast itself is vulnerable to exactly the removal that its wards shut off, an elegant piece of color-pie discipline that keeps the lock from being self-protecting. The "Auras already attached" clause is the giveaway that this was written to answer a specific board state rather than a deckbuilding question: the Beast bails out artifacts that aren't yet compromised, but it won't peel off a Steal Artifact that already resolved. That clause has aged into a quiet historical record of how the era thought about ongoing protective effects, and it's the reason the card still demands a careful read every time it hits the table.