Thinking about the various threads discussing better ways of doing CR got me wondering whether DnDBeyond should include an encounter simulator, and whether that would be feasible. A big problem with CR rating is that it doesn't take into account how particular creatures weigh up against particular adventuring parties, so an encounter that is very challenging for one group can be a cakewalk for another of the same level.
DnDBeyond already includes an excellent encounter builder. You toggle on whichever party will be having the encounter, and then add and remove monsters while it calculates the challenge rating. The problem is that it calculates it using the very basic system from the current DMG...but why does it have to? Since it has all the data, surely it wouldn't be that hard for it to be running simulated encounters behind the scene to give you a much better idea of how challenging this creature or group of creatures will be for this particular party. Would it?
Yes, I believe it would difficult (if not impossible). Because the simulator couldn't take player knowledge, attitude, or skill into account. As an example at the barest minimum...
The party of 7 PCs has 4 characters that have the capability of casting healing magic, and there are 6 Potions of Cure Wounds spread out amongst the PCs. Now the program knows that these spells and potions are available to the party... But for an effective simulator to work, it would have to be able to accurately guesstimate which of the players of said PCs are going to spend their actions using said healing to counteract the damage that the simulator has averaged out as having been dished out at the appropriate times to be effective and not have any PCs lose actions for being knocked unconscious.
But how would the simulator be able to do that? Is it going to know that at this particular table most of those players don't want to waste their turns healing but instead are going to continue to attack because that's more fun? Or will it know that the one player that is all about just healing the other PCs happens to be the one PC that failed its saving throw against paralyzation that was cast at it, and now is incapable of using their actions to heal anyone, thus rendering the party even lighter on recovery? Or maybe some of the players are new to the game and don't even know when they should be forsaking their action to cast a heal spell? And even if they do... which PC is the one best to receive said healing?
These are all things just in regards to a
single aspect of D&D combat that is dependent on what the players choose to do with their turns and has nothing to do with the programming or numbers of "encounter building". Now think of all the multitudes of spells that can be cast and monster actions to be taken... and whether or not the simulator can guesstimate whether those players know how best to use said things and against the proper enemies at the proper times, etc. etc.
Can't speak for anyone else... but I think any simulator is just given people a false sense of security, just like "encounter builders" do. For me... it's better to just become a more experienced DM and rely on personal instincts-- because that specific DM has a better chance at guesstimating what their players are going to do and when, and be able to build encounters that have a better shot at achieving whatever results the DM is hoping to get from that fight then any rando programming person at D&D Beyond is going to.
But that's just my opinion... I could be wrong.