Simple. Make beams a chain of small segments(length based on lag levels, more lag less segments), the starting segment goes forward and slowly curves towards the target, cloning it's self each time it moves. Clones slowly fade over 1 second.Bending beams sounds like it would be more difficult to calculate. You'd need some sort of rope physics or something to beams, instead of them just being a sprite.
Or is that literarily rope physics?