D&D 5E What CR would you give this legendary monster?

[el-remmen]

So, for those of you familiar with the adaptation of U3 - The Final Enemy in the Ghosts of Saltmarsh book, you know that the "Maw of Sekolah," a summoned aspect of the Sahuagin god is a two-headed shark. I found this boring and wanted to create my own weird version of a mutant undersea creature - so my version of the Maw of Sekolah is sharktopus. It only has four tentacles (otherwise it'd be an octoshark!), and I made one from a toy shark and some modelling clay.

Here is the mini I made:

Here are the stats I made for it. I made this version CR9 for the purposes of figuring out its proficiency bonus - but what do you think?
The party is currently made up of four 7th level PCs, an NPC ally who is the equivalent of a 5th level character, and two CR 2 lizardfolk. The monster will spend the first two rounds of the encounter attacking two sahuagin priestesses it it unhappy with for stopping the ritual when the PCs interrupt, but these priestesses will not attack the aspect of their god. (I will probably have them automatically get chomped up to demonstrate the monster's power.

I gave it max hit points. Please excuse any typos in the stat block - I had to make it very quickly while my infant daughter was asleep.

Anyway, what CR would you say it is?

 

[J-H]

That is a neat mini and a cool idea.

With only 180hp and AC 14 against 4 7th level PCs, I wouldn't expect it to survive into round 3 if it spends 2 rounds focus firing the NPCs.

AC CR 5
HP CR 12
To hit CR 10
DC CR 10
Damage (optimal #, tail/bite) 27.5 CR 5

I'd call it more a CR 7-8. It's legendary actions give it no additional damage, and the low AC means it's relatively squishy.
The tentacle grapple is only scary for characters that don't want to be next to it. Ongoing damage of 1d8+5 to a melee character is relatively low, and there's no other disadvantage imposed.

Speed of Sekolah should be changed so that OAs against it either aren't triggered by this, or have disadvantage. Otherwise, it's going to get stuck with the melee PCs and will have a hard time threatening ranged/caster types.

It probably needs some minions as well, maybe a summoned regular shark or two?

Sekolah is all about eating stuff, so I'd find a way to buff the bite attack as well.. maybe two bites per round or the ability to bite right after making a swallow attack? Or maybe it heals for the damage done by its bite attack, or the tentacles have shark mouths on them that heal it for biting damage?

Perhaps the thrashing tentacles also make the turbulent water act as difficult terrain for 1 round (except for sharks) and cause it to provide cover (+5 ac) vs ranged attacks? Make the battlefield more interesting.

 

[el-remmen]

Thanks for the feedback, @J-H.

This is part of the reason why I am so skeptical of the CR system - and I mostly just use it to determine proficiency bonus and XP award. My group are not huge damage dealers (except for the party barbarian) and being underwater makes things a little harder for them (I use underwater combat penalties closer to 1E/2E versions - though the barbarian has a ring that mitigates that). Add to all that a third high priestess in the temple where this encounter happens who is free to attack the party with spells in the first two rounds, and that the party has already had five encounters before this one, a couple of which were kinda tough - and I worry the party is gonna have a hard time of it.

I like the idea of the turbulent water acting as even more difficult terrain (swimming already halves your speed) and acting as cover against ranged attacks. I also like the Speed of Sekolah thing not drawing OAs.

I am considering having the stomach acid damage actually be necrotic and anyone killed that way cannot be raised.

I hope to get an updated version up later today and would appreciate another look.

 

[Quartz]

I am considering having the stomach acid damage actually be necrotic and anyone killed that way cannot be raised.

This is Not Fun. Don't do it.

 

[el-remmen]

This is Not Fun. Don't do it.

Well, I don't want to argue about what is "fun," but this did give me the idea that maybe anyone killed this way has their body digested and their spirit goes to another plane to be feasted on over the period of 1000 years, leading to a potential adventure to free it and then raise the victim.

 

[Quickleaf]

So, for those of you familiar with the adaptation of U3 - The Final Enemy in the Ghosts of Saltmarsh book, you know that the "Maw of Sekolah," a summoned aspect of the Sahuagin god is a two-headed shark. I found this boring and wanted to create my own weird version of a mutant undersea creature - so my version of the Maw of Sekolah is sharktopus. It only has four tentacles (otherwise it'd be an octoshark!), and I made one from a toy shark and some modelling clay.

Here is the mini I made:
View attachment 262121

Here are the stats I made for it. I made this version CR9 for the purposes of figuring out its proficiency bonus - but what do you think?
The party is currently made up of four 7th level PCs, an NPC ally who is the equivalent of a 5th level character, and two CR 2 lizardfolk. The monster will spend the first two rounds of the encounter attacking two sahuagin priestesses it it unhappy with for stopping the ritual when the PCs interrupt, but these priestesses will not attack the aspect of their god. (I will probably have them automatically get chomped up to demonstrate the monster's power.

I gave it max hit points. Please excuse any typos in the stat block - I had to make it very quickly while my infant daughter was asleep.

View attachment 262123

Anyway, what CR would you say it is?

Running the maths, I get...

Defensive CR 17
eff hp = 180 + (4 * 20 legendary resistances) + (3 * 22 foregone damage of one stunned PC each round via Thrashing Tentacles assuming an 18 str 7th level fighter wielding greatsword) = 326
eff AC = 14 + 1 two saves + 2 for underwater advantage = 17

Offensive CR 7
3-round DPR assuming... = 39
(1) Mutliattack, bite + tail smash = 16 + 2 * 11.5 + = 39
(2) Mutliattack, bite + tail smash = 16 + 2 * 11.5 + = 39
(3) Mutliattack, bite + tail smash = 16 + 2 * 11.5 + = 39

Current design disincentives using Swallow... which in turn disincentivizes using lower-damage Tentacles to grapple (because what's the point in setting up 22 avg damage Swallow when other Multiattack option is better?)

eff attack = +9

Total CR = (17 + 7) /2 = 12

Design notes
Generally when I see a monster with significantly higher defenses than offenses, I feel there's an increased burden on the monster to deliver an interesting play experience - because of the potential for the combat to exceed 3 rounds and for the combat to feel more "grindy."

I like your twist on its Legendary Resistances. Flavorful.

I would consider revamping its Legendary Actions to be similarly more flavorful, and to further help it set up the potential for Swallow. Because right now Swallow just isn't worth it for this monster - give up 39 damage now, to probably deal 22 damage at the start of its next turn? You'd need a combat at least 5 rounds long to make that worthwhile.

I would definitely pay attention to the holistic encounter design with this monster. Because the monster is relatively straightforward – it's a hulk that thrashes about, grapples, and (thematically at least) swallows you whole – the rest of the encounter design would benefit from some changing conditions / terrain / developments / hazards / complications to keep a potentially longer or "grindy" combat fresh.

 

[dave2008]

I agree with J-H that the bite attack should be increased. Since it is huge I would start with making it 21 (3d10 + 5) damage. Then I would give it a reaction (or bonus action), something like:

Feeding Frenzy. When a creature ends a turn grappled by the Maw of Sekolah, the Maw of Sekolah can make a bite attack targeting the grappled creature.

PS - Cool mini!

PS #2 - Here is Giant Shark statblock I made (aka great white shark): Giant Shark

 

[el-remmen]

I find it interesting that one person comes up with CR 7 or 8 and another with CR 12 but leaning towards more defensive.

Design notes
Generally when I see a monster with significantly higher defenses than offenses, I feel there's an increased burden on the monster to deliver an interesting play experience - because of the potential for the combat to exceed 3 rounds and for the combat to feel more "grindy."

Combats in my campaign usually last from 6 to 12 rounds and that seems right for my group.

I like your twist on its Legendary Resistances. Flavorful.

I have been working to make each use of legendary resistance at least have a visual aspect related to it, but when possible some small thing the creature has to give up to use it (like a reaction).

I would consider revamping its Legendary Actions to be similarly more flavorful, and to further help it set up the potential for Swallow. Because right now Swallow just isn't worth it for this monster - give up 39 damage now, to probably deal 22 damage at the start of its next turn? You'd need a combat at least 5 rounds long to make that worthwhile.

But it is not just about raw damage. It is about taking a foe out of the fight and the panic that ensues in the group - so I don't see it as giving up much. But I do like the idea of having a reaction that helps set up the bite/swallow, like @dave2008 suggests.

I would definitely pay attention to the holistic encounter design with this monster. Because the monster is relatively straightforward – it's a hulk that thrashes about, grapples, and (thematically at least) swallows you whole – the rest of the encounter design would benefit from some changing conditions / terrain / developments / hazards / complications to keep a potentially longer or "grindy" combat fresh.

I actually imagine the PCs are gonna try to get the heck out of there when this thing shows up. There is even a chance they can goad it to do damage to the sahuagin stronghold they are raiding/exploring. But since this happens underwater, there is a 3D space to play with bound by raised galleries there will be plenty of opportunities for an interesting fight, including retreating into areas only one of it tentacles can reach, etc. . .

This is where we left off. The Sharktopus enters from a dark swirling portal in the ceiling forty feet above.

 

[el-remmen]

A new version. ..

 

[dave2008]

Quickleaf, nice breakdown. Just a few thoughts:

Running the maths, I get...

Defensive CR 17
eff hp = 180 + (4 * 20 legendary resistances) + (3 * 22 foregone damage of one stunned PC each round via Thrashing Tentacles assuming an 18 str 7th level fighter wielding greatsword) = 326

Obviously there is nothing in the DMG about how to figure the stunned condition into your CR and since it is an attack, I would probably add it to the attack CR, but this seems reasonable

eff AC = 14 + 1 two saves

Technically you don't give any bonus AC for 2 saves. Per the DMG you only get a bonus @ 3 or more:

"A monster with three or more saving throw bonuses has a significant defensive advantage, so its effective AC (not its actual AC) should be raised when determining its challenge rating. If it has three or four bonuses, increase its effective AC by 2. If it has five or more bonuses, increase its effective AC by 4."

+ 2 for underwater advantage = 17

I don't see underwater advantage listed in the stat block anywhere. So I think the effective AC is still 14. So combined with the above I get a Defensive CR of 16.

Offensive CR 7
3-round DPR assuming... = 39
(1) Mutliattack, bite + tail smash = 16 + 2 * 11.5 + = 39
(2) Mutliattack, bite + tail smash = 16 + 2 * 11.5 + = 39
(3) Mutliattack, bite + tail smash = 16 + 2 * 11.5 + = 39

Current design disincentives using Swallow... which in turn disincentivizes using lower-damage Tentacles to grapple (because what's the point in setting up 22 avg damage Swallow when other Multiattack option is better?)

eff attack = +9

Total CR = (17 + 7) /2 = 12

So I get (16+7/2) = 11.5, not much of a difference.