I absolutely fell in love with the Spearlauncher from that asshat trio of Iron Maidens in Blackrock Foundry.
I think it was the green glow that did it for me and went quite nicely with the previous expansions Hunter set with regards to the pew-pew laser stuff we got given.
With the fel infestation going on in Legion the green version seemed a better fit than the red and yellow from raids and the blue you could get as a world drop, so this one was my ‘big boi’ Hunter mog at the start before I went back to my more revealing mogs!

Helm: Cybergenetic Mechshades. These do require Engineering to wear (sorry!) but if you don’t have that profession then you could go for the helm from SoO or go for an eyepatch. Or even nothing, it looks good with hidden helm too.
Shoulders: Iron-Studded Mantle. Drop from Ulduar once you kill off the Assembly of Iron. I keep forgetting about them and kill only the Captain Planet dude before running up the stairs!
Chest: Chestguard of Relentless Tyranny. Another bit of raid loot from SoO. There are a couple of variations of it but this is the Normal recolour, red is LFR and blue is Mythic fyi.
Back: None! Cant get tangled up in that now, can we!
Hands: Grips of the Fel Destroyer. Questline to go into Kara with Dadgar to get a Pillar of Creation. Do that and you get these!
Waist: Girdle of the Legion General. Buggers before Heroic Fel Lord Zakun in Helfire Citadel if I remember rightly. Soz peeps, didn’t realise I’d made a set that was so heavy on the raid loot!
Legs: Legguards of Imprisonment. Return to Kara dungeon and you have to do the Beauty and the Beast style Opera Event. There are a fair amount of greens ish coloured legs out there so I would scour your collection to see what you have before going out of your way for these.
Feet: Minelayers Padded Boots.  Juggers in SoO drops these for you on normal.
Gun: Gar’an’s Brutal Spearlauncher. The green is the Normal colourway from Iron Maidens in Blackrock Foundry in Draenor.

Don’t forget there are more transmog/slutmog that can be found here.