troll face
An expression meant to elicit the same raging anger that its namesake activity causes. Usually portrayed as semicircular eyes (upper half exposed) and a smirk or open smile, giving the impression that the person is almost goofily gloating about their victory over your sensibilities.
May also refer to a memetic image from rage comic of a face with a wide, annoying grin, to which the word "troll face" is nowadays associated with.
Not the same thing as doyagao, which is a look of smug self-satisfaction at something impressive that's been done. Troll face is more a sneer of schadenfreude at something that's been done to another person.