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Omeganian
Since: Jan, 2001
21st May, 2018 09:49:46 AM
A long shot: The Demon Seated?
RedScharlach
Since: Jul, 2016
cooljma
Since: Nov, 2010
25th May, 2018 05:10:51 AM
Under the "History of the painting" section of The Colossus Wikipedia article you linked to, there's another version also named The Giant, and that looks like what I was looking for. Thank you very much!
Presumably classic painting of a giant humanoid who looks very depressed. I believe his face is shown (I'm thinking it's similar to the demon from Fuseli's The Nightmare), but his body might be facing away. I believe he's sat on some sort of mountain or a rocky cliff. The scene is very dark and empty, similar in style to darker works of Goya (Saturn Devouring His Son, as an easy example), but possibly more impressionist. Sorry if this is too vague!