Bastion Builder
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Bastion Builder

A free, unofficial planner for the 2024 D&D Bastion rules. Commission facilities, lay them out on a floorplan grid, and run the weekly Bastion Turn — all in your browser, no account needed.

Everything you build is written to this browser only. Nothing is uploaded unless you turn on cloud sync yourself. Export a bastion to a file to back it up or hand it to someone else.

Your library

No bastions in this browser
Create your Bastion Name it, set your level, and start building. Explore a sample bastion See a finished keep — walls, facilities, and all. Someone shared a bastion with me Paste the link to keep it on your shelf — for DMs running a table.
Been here before? ↥ Import from file

Share this bastion

This makes a link with the whole bastion tucked inside it — the charter, every floor, the register of chambers, the household, and how things stand right now: defenders on hand, stores, and each facility's own tallies and notes. Nothing is uploaded anywhere; whoever opens the link sees a read-only copy — and can download a Roll20-ready map of it with one click. Your bastion turns, ledgers, and milestones are left out — a shared bastion is a handout, not your logbook.