The best alternatives to RPGen are AR Grimoire, Super Snail, and Dungeon Mastery. If these 3 options don't work for you, we've listed a few more alternatives below.
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AR Grimoire makes it possible to see your D&D spells on the real tabletop. Go to any area of effect spell and see it in augmented reality! The app also is a full-featured spellcasting app to help you quickly cast spells and easily manage your spellbooks.
With a divine purpose and what remains of civilization, you journey through the past to take down eight Demon Gods. To defeat their apostles and minions, you must join hands with many bizarre beings and collect a variety of items.
Good Dungeon Masters have a lot of notes. But the longer your TTRPG campaign goes on, the harder it is to find the details for everything that's happened! Dungeon Mastery's cross-linked notes are the glue that binds your book of lore together.
Fables.ink is a new platform that aims to replace PDFs while playing RPGs The website has a built-in markdown editor capable of linking contents, you can link a monster or spell anywhere in your campaign or mechanics from other creators. Also, make money)