Champion's Helm

Cheaper to equip than to cast, and that inversion names exactly who this was built for: the irreplaceable legendary creature whose protection is worth one mana to move it. The +2/+2 works on anything, but the hexproof clause only fires when the equipped creature is legendary, and that conditional is the whole design. Bolt the helm onto a token or a mana dork and you get a stat boost and nothing else; strap it to a marquee legend and you get a body that survives spot removal while still answering to your own buffs, sacrifices, and targeted tricks. That last point is where it separates from its peers: Lightning Greaves grants shroud, which protects the creature from opponents but also locks you out of touching it yourself, and Swiftfoot Boots offers the same hexproof at a steeper equip cost. Champion's Helm threads between them, granting protection you can still work around for a single mana of attachment. The result is equipment that does almost nothing in the abstract and becomes load-bearing the moment a deck's plan runs through one creature it cannot bear to lose: a design honest enough to wear its narrowness on its face, with the legendary restriction acting as both the gate and the flavor.