I still dunno which lightning u referring to. Anyways for the finger of death lightning u can use add lightning effect of just edited a chain lightning set it to "finger of death" lightning effect and make a dummy spell.
For the edited colored lightning from above...dats a trade secret dat i wnt tell....kidding, well i dunno how he does it, but here's how i do it in my maps. Use the special effect of the monsoon its a lightning bolt from above. For recoloring it....think about it....think...think....thought about the answer yet? nope? anyways i do it by makin dummy units with that as a model and recoloring them...works for me! haha