How Tough Should I Make Bosses?

[Death_Lord12]

When making a boss, is there a way to guess/calculate if it's going to be too much for the PCs? I'm running a campaign that I want to be challenging but not impossible. CR seems to be more of a guessing game when it comes to calculating it, so I am at a loss of what to do. Even if I am able to calculate/use CR, 1. is it really accurate? and 2. how far above the party level should the CR of the enemies be to be challenging but not overpowering?

I'm mostly looking in help of the areas of NPCs using PC classes, as well as what happens when adding templates and if ECL of the NPC is useful at all for this, as well as finding out CR of creatures not specifically in a book i.e. homebrew or advanced/templated creatures.

Thanks in advance.

[Troacctid]

Try planning out round-by-round how you might expect the fight to play out, and do some math to figure out how likely it is the players die.

[OldTrees1]

For a party of Xth level, I like to either
A:Use a Boss with CR of X+2 and enough minions to make the entire encounter a CR X+3 encounter (if the minions were an encounter on there own they would be CR X+0).
B:Use a Boss with CR of X+1, 2 Lieutenants of CR X-2, and again enough minions to reach CR X+3 (in this case the minions would be a CR X-1 encounter on their own)

Example using Necromancer & Ghouls/Ghasts
Party is 5th level
A: 7th level Necromancer, and 6 Ghouls (CR 1 each, CR 5 as a group)
B: 6th level Necromancer, 2 Ghasts (CR 3 each), and 4 Ghouls (CR 1 each, CR 4 as a group)
Both encounter A and B are CR 8 encounters.

PS: Technically the CR of a group is called an Encounter Level but I still call it CR.

[Death_Lord12]

For a party of Xth level, I like to either
A:Use a Boss with CR of X+2 and enough minions to make the entire encounter a CR X+3 encounter (if the minions were an encounter on there own they would be CR X+0).
B:Use a Boss with CR of X+1, 2 Lieutenants of CR X-2, and again enough minions to reach CR X+3 (in this case the minions would be a CR X-1 encounter on their own)
But how do I calculate CR of something that is not the exact same copy of something in a book?

[OldTrees1]

But how do I calculate CR of something that is not the exact same copy of something in a book?

+1CR per sensible PC level and templates list the CR change. For example a Half Fiend Ghast Fighter 5 might be CR 10 (3 from Ghast + 5 from levels +2 from Half Fiend). If your NPC and their PCs are at roughly the same optimization then this CR is a decent starting point.

With experience you will start to learn to identify when WotC/Pazio estimated wrong.

If you mean something not constructible from existing parts then you would try to compare it to existing parts. For example if I wanted to make a brute that stunned with his blows I would compare it to both Ghast (stun and paralysis are similar) and Ogre (a brute). I might even use a Ghoul Ogre (via the Gravetouched Ghoul template) for the comparison.

[Sayt]

The Bestiaries have an appendix that gives a table of the expected HP, to hit, damage, etc for monsters of a given CR. Might be a good comparison.

[Âmesang]

What's the D&D equivalent of SNK Boss Syndrome?

[Huldaerus]

What's the D&D equivalent of SNK Boss Syndrome?

Drizzt from Baldur's Gate I, Twisted Rune and Kangaxx from Baldur's Gate II.

[Tvtyrant]

Assume that combat is going to be quick, because this is D&D. Your boss needs to deal a frightening amount of damage and/or pile on a huge amount of status effects each turn or it will just die outright.

My experience has been that you need to be able to remove one PC from combat a turn and hamper two more. Remove from combat is drop to 0 HP, throw off a cliff (at low levels), dominate, stun for longer then combat goes, have a pet eat them, etc. Blind/grapple/entangle two more people and then let the fourth tag the boss once. Rinse and repeat on successive rounds.

[Techwarrior]

Personally, when I'm running a game, I go for at least CR = Party level +4 for a true boss monster. If it's more of a lieutenant style, I'll probably run around CR = Party level +2. I still include minions and the like, sprinkled liberally like candies. Those minions are generally very weak.

In my games, a boss, or other end of arc encounter almost 100% of the time taxes my PCs to their limits, and still puts at least half of them in negatives, but without killing them. Occasionally a PC will die, but that's because they did something truly stupid, or the dice hated them. My players know that once the dice are picked up, I'm trying to kill them. Our stories about games afterwards are almost all about the ingenious plan someone came up with last minute to save everyone. Not everyone likes their games that edge of your seat though, and it's a pain to build those encounters. They're worth it for me though. Other games, other styles even, not so much

[LTwerewolf]

But how do I calculate CR of something that is not the exact same copy of something in a book?

Challenge rating is pretty useless when it comes to planning encounters. Completely ignore CR and go from there. Pick things that feel challenging and reasonable.

[Dousedinoil]

Although I do increase the CR or add minions, I don't think always best way to challenge players. Here are a couple things I do to make encounters more memorable and fun:

1. Have a mechanic/puzzle of some sort that the PCs need to figure out. Perhaps their are different pillars that light up with either fire, electricity, poison, ice, etc every round. The boss can only be hurt by that type of damage.

2. Give the boss a surprise round. It's not like they are always going to be lounging around waiting for the PCs to ruin his plans without knowing they are coming.

3. Adjust the terrain to be more favourable for the boss. Maybe he benefits from hiding in the shadows.

4. Have an objective that puts the PCs at a weakness. Have a hostage that they need to rescue and see them throw tactics out the window.

5. Keep on roleplaying! Even if you're fighting it's always hilarious when the boss offers the first player to join him a massive gold reward to betray his friends. Lookout if their is a chaotic character in the group!

[Jay R]

And if the boss turns out to be too easy to kill, invent the shadowy figure behind him who's the real boss. By the time the hero can take Darth Vader, you need to be ready to introduce Palpatine.

[Âmesang]

That actually makes me imagine the shadowy figure literally appearing behind the "big bad" after the guy falls, like he teleports in or was invisible the whole time and just appeared to give his villainous monologue. :smalltongue:

EDIT: That, in turn, makes me imagine a black knight type character who's raging in fury and pain… and it turns out his armor is the only thing keeping his power in check. Defeating him destroys the armor which lets his "true self" out, leaving him relieved, calm, and more focused for villainy. Hmm…

[Dousedinoil]

I always joke with my players about characters that drop too quickly. I usually throw in "now for my final form!" or "this isn't the last you've seen of me!" just to keep the players guessing.

[BWR]

Short answer, you have to know how powerful the PCs are and how good the players are and plan accordingly. There really is no other answer.
CR can at best give you a rough estimate of where to start.