[You did not provide any information about the manga.] If you can provide a specific name or description of the comic, I would be happy to help you determine the source of the comic.
I'm not sure which comic you're referring to. If you can provide more information such as the story of the manga or the author of the manga, I will try my best to help you answer your questions.
Bloodshot originated from Valiant Comics. It's a popular comic series known for its action and sci-fi elements.
Spawn is from a comic of the same name. It was developed by Todd McFarlane and has gained a significant following over the years. The comic features complex storylines and unique characters.
Morbius is part of the Marvel Comics stable. His character has been featured in various Marvel comic publications, often interacting with other popular Marvel heroes and villains.
Invincible is a comic created by Robert Kirkman, Cory Walker, and Ryan Ottley.
It depends on your expectations. Maybe it is, maybe it isn't. It's subjective.
Harley Quinn is from DC Comics. She first appeared in Batman: The Animated Series and later became a popular character in the DC comic universe.
The story of a train from the comic might be a fantasy where the train takes passengers to magical places. Or it could be a historical account of an important event that happened on a specific train.
Spawn is from a comic book of the same name created by Todd McFarlane.