It's a headdress, though - Sorceresses in FF8 wear horns as part of their aesthetic
Halvar, God of Battle assists in cheating around equip costs, which can put a powerful Equipment onto a creature for free that would otherwise cost a hefty amount of mana to do so
So if paper rarities do count, I'd like to start playing with Hymn to Tourach and High Tide and Blue Elemental Blast, please
It once dominated multiplayer tables so much that False Cure became almost a requirement
These cards are printed in extremely limited quantities, and they're unique to the person gifted them - to the point of including the individual recipient's name
And bouncing has a lot of flexibility as a way to survive removal or blocks, adding a useful tempo element, reloading a creature with a powerful enters-the-battlefield trigger, dealing with auras and so much more