Sephirot The Fiend  is one of the three Warring Gods "Warring Triad"

They are a group of three Primals from Final Fantasy XIV.

Sephirot will be the first of the three that you'll face.

Source: http://na.finalfantasyxiv.com/lodestone/topics/detail/3c4e6201ba7fa8d1e15f9b5acf674a9e22c6ff1d

http://finalfantasy.wikia.com/wiki/Sephirot

I recommend you give the free trail a shot. FFXIV is not only an MMORPG, because before that it is a Final Fantasy.

if you stick only with the main story, and don't bother doing anything else, you'll be telling yourself this is more Final Fantasy than the other Final Fantasy games you played. I guarantee it.

I would love to be playing FFXIV still, but the content cycle is trash. Here's hoping 4.0 brings some massive revamps.

Damn, wish I had time for MMOs. But unfortunately o don't.

Possible FFIV, boss as boss in The Antitower FFXIV.

If you notice in the bottom picture, these are most likely Calca and Brina dolls.

In FF4, they were able to merge together to form an even bigger boss.