Challenge collection

bad quality, low quality, extra fingers, bad_anatomy, extra_arms, lowres, extra hands, extra digits, fewer digits, loli, child, censored, bad_proportions, bad_perspective, missing digits, displeasing, signature, username, watermark, logo, unclear, same person, score_5, score_4, score_3, score_2, score_1, worst quality, scan artifacts, monochrome, greyscale, twitter username, jpeg artifacts, 2koma, 4koma, guro, extra digits, fewer digits, jaggy lines, same person, multiple girls, 2girls, same girl, 2 guys, multiple guys, mmf, ffm, group, Victorian, old timey, background figures, other students,