If you are looking at the features included in such an edition, "solid" usually implies:
Be cautious when downloading .rar files from unofficial sources, as these are not supported by the developers and may contain malware or cause game instability. Helldivers.a.New.Hell.Edition.part2.rar
In the context of the Helldivers community, a typically refers to a significant gameplay or mechanical addition that provides stability, balance, or a highly requested quality-of-life improvement. Possible Contexts for this Pack If you are looking at the features included