If he uses
the dark Jedi he’s definitely a dark Jedi since it’s a broad term for dark
force users.If he had
some level of Jedi training, uses both light and dark side of the force he’s
also a grey Jedi. Grey jedi usually don’t pick a side. They see the force as a
whole, so to them is not a matter of picking a side (light/dark) but of
embracing the Force as a whole, without distinctions. Grey Jedi don’t “go dark
side”, they use it but they never “go evil” like the Sith.If you
should call him a Rogue Jedi is up to you. it’s not an official title. There’s
no real specification of that makes a Jedi a Rogue Jedi or how they are
different from grey Jedi. by definition, the title Rogue suggests a Jedi
disconnected from the order so I see it as another way to say ex-Jedi. by the same definition your muse might no be considered a rogue Jedi since he’s still part of the Order. To exemplify
it:Dark Jedi =
anyone who uses the dark side despite
of any political affiliation, including darth vader, palpatine, ventress, maul,
the nightsisters, the inquisitors, etc.Grey Jedi = beings who used both
light and dark but were never corrupted by the dark side, jedi who used both sides and jedi known
for disagreeing with the Jedi Council (Qui-Gon and the father).Rogue Jedi = Jedi no
longer affiliated with the Jedi Order (Anakin, Dooku, Ferus, Ashoka,
Barriss, etc).So if your muse is a Jedi who uses both sides of the Force but haven’t been fully corrupted by it then he’s probably a Grey Jedi.