DM Helpmate is an offline, downloadable DM (Dungeon Master) companion for Windows featuring an interactive database, links to spells and spell slots, attack and damage dice rolls, skill checks, filtering by parameters and tags and much more.
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D&D Beyond Alternatives
D&D Beyond is described as 'The official digital toolset for Dungeons & Dragons fifth edition. Twitch integration and a massive online compendium of official characters, spells, items and more provide an easy to use system with everything dungeon masters and tabletop D&D gamers' and is a virtual tabletop in the games category. There are more than 25 games similar to D&D Beyond for a variety of platforms, including Web-based, Windows, Android, iPhone and iPad apps. The best D&D Beyond alternative is MasterScreen, which is free. Other D&D Beyond like games are Roll20, Fight Club 5th Edition, Rolisteam and Dungeoneer.