It's a bit of an out-of-the-box thought. 😅 It's a TTRPG and not a digital sandbox. But of course, in some way, the ultimate sandbox.
There's a whole community of people who write adventures (campaigns, one-shots) and lore, make mini's and terrain (model, 3D print, paint), craft dice and gadgets, design characters, invent items and monsters, tell stories. Probably/possibly not the best fit for SBG but a big creative game community for sure!
PS ETA: and maps! Top-down grid or hexagon tabletop maps for printing or digital screen.
