Katakana transliteration is a bit too flexible, so it sometimes depends upon authors/writers.
For example, it was ジーフリト for Siegfried that a J translation of the Nibelungenlied which I read before. But ジークフリート sounds more common Katakana transliteration, I suppose.
Like you said, it is just a game stuff, maybe fantasy one?, so the person took エリューズニル as a name, I mean, エリューズ for its first name, and ニル for its last one. Then s/he added ・ between them.