Id rather NOT use something that will share my personal details with questionable institutions, but deepseek won't remember anything I typed in my current session (and for the libs out there, no, I don't care if China has my personal details; it's not China that can and might use my personal details against me).
Id hate to craft a whole setting in shadowrun only to have to do it again next time. I've been working in Qatar for over a decade and wanted to craft a Qatar-based game (for which by the way, deepseek has gone above and beyond in crafting a shadowrun Qatar; they know about the local traditional attire and suggested shadowrun items themed around them without prompting, and locales they rewrote to reflect a shadowrun aesthetic, and it's calling the underground hacktivist resistance 'silk ghosts' (it does a silk road thing throughout)). I only suggested robots occupy most jobs and it crafted a Qatar where robots are 70% of the workforce while the locals are either execs or destitute, and the (in real life nationally owned) energy and oil company are now privately owned by 'Sustainitech'.
After this impressive world building all I can think is I really don't want craft all this from scratch every time.
If you want a solo DnD you should understand that you're not getting DnD but at best a co-written story in second person perspective
Look into SillyTavern and Worldlore in the docs
Understand that this will actually take hours or even days to set up, and in the end, it'll still be an AI that is ass at its job, something you have to fix every few messages
You should also know that self-hosting ai may not be enough, 4k tokens is bare minimum and even that usually takes up 8gb of vram, DeepSeek API is cheap, use that.