. ▁The ▁Green ▁Mon key ▁Sp ell ▁proves ▁irre vers ible ▁and ▁has ▁to ▁be ▁transferred ▁to ▁somebody ▁else . ▁In ▁this ▁case ▁Mrs . ▁Y oop ▁who ▁becomes , ▁and ▁must ▁now ▁stay , ▁a ▁green ▁mon key . ▁She ▁is ▁a ▁Y ook o oh oo , ▁a ▁special ▁kind ▁of ▁w itch , ▁" an ▁Art ist ▁of ▁Trans form ations " ▁whose ▁en chant ments ▁are ▁extremely ▁powerful . ▁The ▁other ▁Y ook o oh oo ▁in ▁the ▁O z ▁books ▁is ▁Red ▁Re era ▁in ▁Gl inda ▁of ▁O z . ▁ ▁Both ▁Y ook o oh o os ▁are ▁special ists ▁in ▁mag ical ▁transformations ▁and ▁are ▁solit ary , ▁anti - social , ▁and ▁fier c ely ▁independent ▁The ▁T in ▁Wood man ▁of ▁O z ▁is ▁a ▁r ar ity ▁in ▁Ba um ' s ▁O z ▁canon , ▁in ▁that ▁the ▁author ' s ▁manuscript ▁of ▁the ▁book ▁exists , ▁and ▁reve als ▁the ▁changes ▁that ▁Ba um ▁made ▁for ▁the ▁printed ▁version . ▁Ba um ▁re vised ▁his ▁original ▁to ▁make ▁Mrs . ▁Y oop ▁more ▁sin ister ; ▁and ▁he ▁originally ▁called ▁Mrs . ▁Y oop ▁a ▁" Wh isp " ▁( an ▁otherwise ▁unknown ▁term ▁in ▁the ▁universe ▁of ▁O z ) ▁rather ▁than ▁a ▁Y ook o oh oo . ▁ ▁Sa wh or se ▁ ▁The ▁Sa wh or se , ▁sp elled ▁" s aw - hor se " ▁in ▁some ▁of ▁the ▁books , ▁is ▁a ▁character