If you are looking for lots of guide and tips for any video game you play you will find it in this guide and site :)
Mirrors, portals. [Mariusz Lewandowski]
Time Portal by Thomas Stoop. Character Concept Art Illustration
Portal, GLaDOS, Chelle, Video Game, Artwork, Fan Art Portal Cake by ChasingArtwork
Portals. Waterfall, Ruslan Safarov on ArtStation at https://www.artstation.com/artwork/OP298?utm_campaign=notify&utm_medium=email&utm_source=notifications_mailer
The Hoover Building on Western Avenue (A40) in Perivale, West London, is an example of Art Deco architecture designed by Wallis, Gilbert and Partners.
Mini Wall Portals & Companion Cubes. Nice, detailed tutorial that can be adapted to a lot of different crafts.
Makes me think of the strange rock formations on the island in Call of Cthulhu. A portal to strange realms?
Pinterest: @WhyYouTagginMe; a big wow for that ...