I built a free encounter simulator for DMs, with D&D Beyond PDF import

Hi DMs,

I messaged the moderators first since tool posts can be a grey area, so happy to move/delete if this belongs elsewhere.

I built BattleCast, a free D&D encounter simulator for testing combat encounters before a session:

https://battlecast.gg

Instead of only relying on CR math, you can place monsters and heroes on a tactical grid, watch the fight play out, or run Monte Carlo simulations to get a rough sense of how dangerous an encounter is.

I recently added D&D Beyond character sheet PDF import. If you export a character sheet PDF, BattleCast can read the combat-relevant fields locally in the browser: HP, AC, speed, ability scores, weapons, attack bonuses, damage, and modeled spells.

A few caveats:

- It is unofficial and not affiliated with D&D Beyond or Wizards.
- It does not support multiclass characters yet (it defaults to one class as a fallback)
- It does not model every feat, subclass feature, or magic item passive.
- Player tactics are approximated by simulator, so it does not account for full player creativity

I’d love feedback from other DMs:

Would you use something like this before a session?
What would make you trust or distrust the results?
What is the most important thing it currently misses?

Looks really good need to test more though

This sounds really cool, and definitely something I would consider using.

The main thing I would want would be the facility to put custom monsters into it. For standardising, I would recommend using the Tetra-Cube monster stat block creator, which can export monster files for saving & loading.

May require a quick interaction with the app at the start to say "on a hit, DC 15 con save or grappled + paralyzed condition" to cut through the wordiness of some abilities, which I would be more than happy to do if it let me run a load of simulations and determine the outcomes. This would be immensely helpful for balancing homebrew monsters!

Thanks for pointing me to the Tetra-Cube monster stat block creator - I was not familiar with the tool, but definitely something I will want to include.

At the moment I added custom import and export, and went with a more-less basic template:

The cool feature is that once you define your monster there, you see it actually participate in grid based combat.

This is really cool, here's some suggestions from my time messing with it:

Make AOE damage trigger all at once because it adds a lot of waiting time while looking at the battle animation

Add a way to import our own maps or at least add cover/terrain elements

Individual tactics for each creature

Not really as relevant but the pit fiend scenario is not even an uphill battle, it's just a cliff.

3+ Teams or free-for-all battles

Love the ideas- the AoE is such an obvious fix- it was annoying me but I somehow didn’t think about it!

I am messing with it every evening pretty much.

Maps should be easy to add, free for all and teams are quite a lot harder as the whole battle logic is around 2 teams…

I need to re-visit scenarios as after lots of ai fixes some of them are super imbalanced by now.

Thanks for feedback!

The lich specifically seems to skip its turn a lot.