玄武門之變

Xuanwu gate coup of June 626 in early Tang, in which Li Shimin 李世民 killed his brothers, seized the throne from his father as Emperor Taizong 唐太宗

black / mysterious

Black Tortoise (the seven mansions of the north sky) / (in Daoism) God of the north sky

surname Wu

martial / military

gate / door / CL:扇[shan4] / gateway / doorway / CL:個|个[ge4] / opening / valve / switch / way to do something / knack / family / house / (religious) sect / school (of thought) / class / category / phylum or division (taxonomy) / classifier for large guns / classifier for lessons, subjects, branches of technology / (suffix) -gate (i.e. scandal; derived from Watergate)

(possessive particle, literary equivalent of 的[de5]) / him / her / it

to change / to become different / to transform / to vary / rebellion