Use your skills to make the monster fall in the trap. Get rid of some blocks and place the monsters in the most dangrous spots to get them. Use your mouse.
When all the defense walls have been conquered you are the only one standing in the way of the bees. Defend your hive! Aim with the mouse and take the shot. use A,S,D,W to move it and press 1,2,3,4 to change the weapon.