Crystal Golem

Every turn it survives, this 3/3 simply phases out at your end step and phases back in before your next untap. That recurring disappearance is the entire evaluation. A phased-out permanent counts as gone for all purposes, so during your opponent's whole turn the Golem cannot be targeted by their removal, swept by a board wipe, or chosen for a sacrifice effect; it slips back ready to attack each cycle. The price is paid on defense: while it is away, it sits out your opponent's combat entirely and cannot block, so you are spending half the rules-engine clock with no body on the table. Trading the defensive half of a creature's job for near-total immunity to interaction on the off-beat was an unusual bargain for a four-mana artifact, and the body underneath is plain by design. The keyword that powers it would lie mostly dormant for years before returning, and most later phasing cards treated the timing as an upside rather than a tax: blink-style protection, untap shenanigans, evasion windows. This Golem belongs to the period when designers were still feeling out what phasing meant, framing it as a drawback bolted onto an otherwise vanilla artifact and asking players to reckon with a creature that periodically refuses to occupy the board at all.