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巳 — in
异 a stylised contraction of the masked figure's head. Strict etymology: traditional
異 pictured the mask itself as
田 on top, with legs + two raised hands below — a costumed ritual performer who looked 'other.' The 1956 reform compressed the mask-on-head into a
巳-like silhouette; here it is best read as 'the strange masked figure on top' rather than as a snake.