it depends what you want.
Make the object have a 'bullet' behavior.
If you want it to just move towards the mouse, just set the bullet speed to whatever you want and then every tick set the angle towards position of mouse_x, mouse_y.
if you want it to move at speed relative to its distance from the mouse, do the same as above, but every tick set the bullet speed to distance(object.x,object.y,mouse.x,mouse.y) / modifier + modifier