Thank you

Seeing as "Death Gate" is now available for sale on GOG.com, I can confidently say the answer to your question is "no." The copyright is still held (either by Piko Interactive or Legend Entertainment, I'm not clear on which). Abandonware - a term of dubious legality - refers to software that is no longer supported or sold by its publisher. While arguably "Death Gate" might have been abandonware prior to its re-release on GOG, that is no longer the case. If you want to legally play the game, you need to cough up the 6 bucks for the privilege.

Personally, I'm not a huge fan of "Death Gate" but I paid the pittance to encourage Piko Interactive to license and re-release other Legend Entertainment games that I /am/ interested in (mainly, "Mission Critical", which is not only one of the best hard sci-fi games out there, but a pretty good adventure game too). Legend Entertainment also had a number of other memorable titles I'd like to see on GOG, such as the Spellcasting series, Eric the Unready, Superhero League of Hoboken, and Wheel of Time. These are all worthy titles so if you are interested in playing any of them, it's worth it to support the publisher.

Well, now that it's been removed - this is probably because the ownership has changed and doesn't have an agreement with GoG - so I would say the answer is probably still "no."

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https://www.gog.com/wishlist/site/for_dos_games_if_theyre_scumvm_also_include_original_files