Every key and chest is drawn in the same two pixel colors — black and white. Rarity isn't a color swap, it's a redesign: more teeth, more studs, more spikes as the tier climbs.
Five tiers, five distinct silhouettes.
Solid bow, one tooth.
Ring bow, straight shaft.
Diagonal shaft, one tooth.
Gem-set bow, two teeth.
Spiked corners, gem, three teeth.
The same rule applies to chests — plainer at common, more ornamented toward legendary.
Plain box, no lock.
Lid, hinge line, small lock.
Centered lock plate.
Corner studs added.
Domed lid, spikes, studs.