!!WARNING SPOILERS FOR AGIT AND SW!! Okay the spoilers aren't that bad because they've been morphed into something else entirely by my headcanons but you can still get some pretty big spoilers
This is roughly what Vader looks like if he's in battle:
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(I'm still not a great artist at this point in time so don't judge me too harshly on the art)
If it's something more casual (or just not a battle) he'll wear a black outfit with either reds/blues or browns that's got at least 20 wepons hidden on his frame and he can move in. Usually with a hood but not always. The blue he has is 501st blue while the red reminds people of fire and lava.
In this au Vader died on the Death Star, his home realm is called Star Wars. Vader becomes a ghost with and doesn't remember any of his life, he explores for thousands of years (he's a ghost, time is longer here, you're practically an infant for the first 50 years of your afterlife for example, and ancients mature even slower), gaining control of his powers, learning to fight and different forms of weaponry from various ghosts, even pretending to be mortal and go to earth a few times (one of which was Achilles), he finds out he's an amazing fighter and after another 200 years most of his memories of his life come back. He also realises he's an ancient, specifically of war.
Also Dan is ancient of destruction I think??? He is a psychopomp (a figure who leads dead souls to the afterlife) only instead of dead souls he find people who're meant to be dead but are somehow still alive and kills them with a scythe that showed up when he took on the job, it makes the cause of death appear to be whatever they should've died from. He isn't an ancient but is almost as powerful as one, his domain as his role as psychopomp of those overdue is over all the souls he collects and all the souls who need to be collected.
Also AGIT? Vlad got redeemed? No he didn't, yeah he did a good thing, but that wasn't enough. He also kind of freaks out when he realised what he did and suddenly has all these conflicting feelings (also he's only been dead for like 30 or so years at this point, he's a baby) and just locks himself in his haunt (his haunt is his lab, his mansion/castle is the Dairy Kings haunt).
And by the way, this is redeemed Vader, he's okay now, not good, but like, bad good, an anti hero almost. He does things considered bad by most people (murder, war, ect) but is doing it for good reasons. So he's good. Mostly. He's considered good by ghost standards because they can come back from far worse injuries than human.
Vaders isn't a halfa but does have two forms, 'bad' and 'good' although they are really closer to dark emotions like anger, jealousy, insanity and light emotions like pride, amusement, love.
He can also put on a human disguise like many powerful ghosts can but all it really is is a badly done disguise and any well done spell or magic user, or even someone who's just a little contaminated or looking to closely might realise anything from 'he's a little off' to 'HOLYSHITTHAT'SAGOD'. He figured out his human disguise on his first run in a mortal realm where he met that places version of the GIW.
