Mouse hold-movement combined with WASD for top down game

Hey, I’m new to the engine, I’ve watched tons of how-tos and other tuts, but still, I am unable to make my character move with mouse movement additionally to the basic WASD.

What I want to do: I want to have a similar type of movement that Spiral Knights have. Basically: You can move with WASD or just with the mouse input, but not like point and click then wait till a character gets to the location, it moves only when the LMB is held. I need to be able to combine these 2 types of movement as the original SK had. And also if I press the opposite direction- movement changes direction with priority to the last pressed direction.