FOLLOW-UP: It occurs to me that, actually, plenty of humans could definitely clear my "higher bar." All you need to do is memorize a 64-character hex string, wh

FOLLOW-UP: It occurs to me that, actually, plenty of humans could definitely clear my "higher bar." All you need to do is memorize a 64-character hex string, which is difficult but completely doable using a memory palace or similar technique. Practically speaking, though, this isn't something that the average person is capable of doing. Even memorizing one hex string, let alone multiple (for each of your friends), requires a lot of effort for little benefit. Furthermore -- if you can memorize the hex directly, you don't need the avatars in the first place! :P