No they were not. https://store.steampowered.com/app/270050/Quest_of_Dungeons/ you can see the assets in use in a much older game as well. And the reason for that is because these assets are made by Oryx Labs, offered as royalty free purchases from their website. https://www.oryxdesignlab.com/ Specifically, it is the 16-bit fantasy tileset pack.