Triangular deadzone for skills if mouse cursor is near top-left/top-right corner

There are two triangular deadzones near the top-left and top-right corner of the screen. If the mouse cursor is in one of these deadzones, most skills will fail to cast. When the mouse cursor is moved just outside the deadzone, the skill can be cast again.



Examples of skills that fail include Flame Dash, Smoke Mine, Frost Bomb, Frostbolt, Ice Nova, Winter Orb, Vigilant Strike. (Skills like Steelskin or toggling auras still work. "Move only" still works.)

The bug occurs regardless of whether "attack without moving" is checked on or off. It also occurs regardless of whether the skill is bound to a keyboard button or a mouse button.

The size of the deadzone appears to be influenced by terrain elevation but I am not sure exactly the relationship.