What minions would balance the final Curse of Strahd encounter with this party?

Question

I'm a fairly new DM and have trouble properly balancing combat encounters sometimes. For the final battle in Curse of Strahd, the players have managed to

secure the help of van Richten and Ezmerelda (she was the card reading). They also have the tome, sunsword and holy symbol.

The party consists of a sorcerer, monk, warlock, eldritch knight and cleric, all level 9 (I could make them level 10 before hand as well).

Of course, Strahd would

know this is what he is up against, and although prideful, would

likely have help with this fight. How many wolves/bats/vampire spawn would make a fight like this hard, but winnable?

Answer 1

We can't tell you

Balance doesn't come from the monsters you put on the table, it comes from how you play them and how your players play their characters.

If you play Strahd as written, a clever and diabolical opponent with centuries of experience of wiping the floor with adventurers then, unless your players are very, very good and highly experienced then they are dead PCs walking. See How can I play monsters and NPCs up to their potential?

For example, Strahd has these abilities that will make things really tough on the PCs:

Legendary Resistance (3/Day), Regeneration, Spellcasting particularly detect thoughts, animate dead, nondetection, greater invisibility, polymorph, animate objects, scrying), Spider Climb, Charm, Children of the Night (1/day).

Used judiciously, with that on the table, I could kill the party you describe with no trouble at all. Basically, I'd pick them off one by one.

Given the gothic horror nature of the adventure this would be a very nice end to the campaign: just when they feel themselves strong enough to take on the BBEG he teaches them a lesson in hubris and ruthlessness. Classic!

Alternatively, I could put a dozen minions on the table with them., employ them stupidly and give the party an easy win. but that would be boring.

You have the power

Strahd likes to play with his food so it is completely in character for him to devastate the party, gloat and walk away, just so he can do it again tomorrow.

Or weaken the party and then leave them to his minions in a number that you are confident the party can deal with even in their emanciated state.

And here is the little DM secret you need to know. Come closer, I'll whisper it.

^{Monsters die when you want them to - hit points are a tool but there is nothing to stop you saying "It dies" even if it has a gazillion hit points left.}

Answer 2

Here's my background: I haven't run Curse of Strahd in 5e, but I have run Expedition to Castle Ravenloft in 3.5e, which also has a final battle against Strahd.

Here's my answer: as Dale said, it's very difficult to predict in advance what will be a "difficult but winnable" encounter. Quite a lot depends on the circumstances -- who's surprised who, who's got what spells active, what sort of tactics Strahd uses, and how well-optimized your player characters are.

If your goal is just to have the one combat be interesting, the thing that works is to eyeball the reinforcements on-the-fly. When the players attack Strahd, start the battle with just a few allies for him, but tell the players that he's calling for more help. Every round, a few more monsters show up. This lets you adjust the difficulty on-the-fly: if Strahd seems to be doing poorly, he gets more reinforcements, and vice versa.

What I did when I ran the game was to have Strahd fight the party several times, at various points in the castle. Usually they'd defeat him, but sometimes they'd run. When he died, he'd just mistform back to his coffin and respawn and attack again after an hour. So the real "boss battle" of the game wasn't Strahd, but rather the catacombs full of traps and minions that surrounds Strahd's real coffin. Then when the party got close to Strahd's coffin, I used the trick described above: every round more monsters showed up, until they fought their way to the coffin and killed Strahd permanently.