From Unicode proposal L2/20-059 by Ken Lunde containing Han ideographs
considered "strange" in 12 categories:
Asymmetric, Bopomofo, Cursive, Fully-reflective, Hangul Component,
Incomplete, Katakana Component, Mirrored, Odd Component, Rotated,
Stroke-heavy, Unusual Arrangment/Structure.
Pick 4 mostly random characters, preferably from different CJK blocks of
increasing version up to extension F.