暗

dark, gloomy, dark (in colour), dull, depressed, dispirited, sorrowful, bitter (as in a dark past), unclear, unfamiliar, unknown

assassination

to get dark, to end, to come to an end, to close, to run out, to be sunk (e.g. in despair), to be lost

light and darkness, light and shade

implicitly

reef, sunken rock

code, password, cipher

hint, suggestion

total darkness, pitch dark, bleak future, poor prospects

total darkness, pitch dark, bleak future, poor prospects