Years ago, a lot of concept art from the first game was released and published on this webpage, but apparently there's more!
The first one is personally my favourite one, It gives me the feels of a circus billboard from the mid 90's (Well, I was born in 1996, so I don't know if that's how a circus billboard would look like in those years, but I suppose it would be something like that).
Look at that early russian-esque TWIN SEEDS tower!
(Notice that the game was originally named NiGHTS: Fly into the dream paradox...)
I'm sure that both of them are Reala.
Well, I asumed that the pink guy above was Reala, because it looks like the other prototype Reala at the right corner.
You already know this one, except that NiGHTS's jacket is green and his legs are painted entirely in a single shade of purple.
Elliot and Claris:
Before they had NiGHTS's 3D model done, they'd use hand-made illustrations.
Clawz.
Source: starryindigo.tumblr.com
Acording to the description of these images, all those concept art pieces where shown in Sega Magazine 3 from January 1997.
What do you think?
Please, admins, put them in the concept art section of this webpage. <3