This Zły icon is made in Material Design style developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 4,300 icons, all in the same style and quality.
This is the Icon for Angry. It is a circle shaped face, with teeth showing in a half circle grimace. The eyes are ovals that are slanted downwards, with two lines above the eyes slanted downwards also that make up the eyebrows.