Force Lightning seems to have many different variants that have different effects and intensities. The classic blue is what is used by most darksiders, including Count Dooku, Starkiller, and many others. Palpatine's lightning was purple mized with blue, and it clearly seemed more potent than the blue. Yoda could absorb Dooku's blue lightning, but he couldn't handle Palpatine's purple. Red force lighting is seen in TCW, used by the Son, in TFU use by Luke, and in a picture of Darth Tenebrous. Luke and Jacen both used green lightning in the NJO, in the latter's case it wasn't lethal, in the former's case it was. Jaina used black lightning in SBS and DJ, and it was lethal. So, what's the meaning of these different colours, does it signify power, alignment, or something else entirely?
I'll point out that Luke's green lightning wasn't necessarily lethal, either. Those he struck with it fell down; there's nothing saying they were killed. In all likelihood, it's identical to Jacen's green stun lightning -- which, I'd argue, needn't have anything to do with Force lightning proper. It's just a visual light effect on a stun power (just like in KOTOR).
Havac: I just scanned that passage, and it turns out that you may be right. There is no real evidence to support that Luke's lightning actually killed the slayer. But going back to the intensity thing: Purple lightning is stronger than blue, and we see that, Yoda can absorb Dooku's but not Palpatine's. So where does Red Lightning figure into this? Well, we know that the Son used it, and he is supposed to be the embodiment of the Dark side. But Luke also uses it with almost no training in TFU. So how does red lightning figure into the power schemes and Jaina's black lightning. Arawn Fenn: Very amusing, that's what I was going for in the title.
Luke's use of red lightning in TFU is in the alternate universe section so it might just be because it looks cool. Kyp Durron also used red lightning while under the influence of Exar Kun -- or it could have been Kun using Kyp as a conduit, I don't remember.
Darth Maul also used red lightning in TPM video game. But really, color of lightning is just a stylistic thing; I don't think it has any effect on the powers at all. For example, all lightning in TOR is purple, to differentiate it from the blue "lightning" that comes from T7 and the trooper class. All Sith use purple lightning, from the Sith Emperor to Revan (who had used blue lightning in the KOTOR game), to Darth's, to Lords, to minor acolytes that can barely use it effectively. I also believe Palpatine's lightning was blue in TFU, and was powerful enough to force Starkiller to destroy himself. Darth Plagueis also suggests that the dark side might have different levels of prevalence at different points of time; could just be that it manifested itself as purple lightning in the time of TOR.
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according to the Plagueis book wasn't the lighting that Sidious used in ROTS considered to be the sith variation ?
