Physics sometimes feels off and makes aiming tricky. I think the gravity is weird. The fast-paced action demands quick reflexes and precise mouse aiming to avoid getting hit and to manage your ammo wisely during chaotic bursts of shooting in the browser.
Clicking to fire and moving to avoid shots is the main goal. You use the mouse for aiming, and spacebar for quick reloads sometimes. The mechanics are wonky, but the graphics are neat enough to tell what is what. The servers can lag, which is annoying.
Often i find myself just clicking and dragging for quick shots. The controls are simple, using the mouse for precise aiming, which is kinda weird anyway, and the spacebar for reloads. Their mechanics can be a bit tricky with the physics, but it is all about fast reflexes.
Quick tip: practice your aiming speed. I discovered that using the mouse for precise aiming is better then just clicking wildly. It helps you stay alive longer and not waste ammo on missed shots. The mechanics are fast, and the physics is wonky, so keep moving.
Reflexes are the main thingy here. You have to click and drag the mouse for precise aiming, and sometimes use the spacebar for a quick reload. The graphics are simple but neat, and the physics is wonky, which makes the shooting stuff tricky but fun. No deep story just chaos.