D&D 5E lowest level to fight a marilith

[Tales and Chronicles]

Hey guys,

I've been lurking for a while on this forum, but this is my first post. I want to surprise my usual group with a campaign based on Legacy of the crystal shard + the Icewind dale I video game scenario (Balhifet being under the control of the remnant of Crenshinibon instead of the full thing, because of the timeline restriction).

In the game, the party faces a rogue marilith named Yxunomei at rather low level in a temple full of yuan-ti. Now, say I want a party of, lets say 5 PCs, to face the CR 16 marilith. What minimum level should they be to have a deadly encounter but not a TPK?

I also had in mind of refluffing a Yuan-ti nightmare speaker CR 7 + 6 CR 1/4 flying swords rotating around her instead of being wielded, with maybe the addition of a yuan-ti cultist to buff/heal her.

 

[FormerlyHemlock]

Hmmm, deadly encounter but not a TPK?

Level one. Courtesy of lots of grovelling and some fast-talking, and probably a promise of a favor or two.

 

[LordEntrails]

Well, if you look at the DMG, a CR16 creature is 15,000xp. If it's alone the challenge multiplier is 1. So, if you finish up and do the math (divide by 5 characters), reference table on pg 82. That makes it a deadly encounter for characters of level 10 (2800 xp/character).

In my experience, those tables are pretty generous to the party. Depending upon your players ability for tactical combat, the characters cohesion and how they are outfitted and prepared, my players could probably beat this with 5 characters at level 8.

But, the risk of a TPK would be there, and character death would probably be guaranteed.

 

[FormerlyHemlock]

More seriously: it depends entirely on the details of your party and the tactics they use. You know those better than anyone. You also know better than anyone what you mean when you say you want a "deadly" encounter. Do you mean that you definitely want to kill at least one PC? Do you just mean that you want the potential for PC death to be there if they mess up?

It's more than possible for a four-man party of level 5 PCs to kill a Marilith, but if your PCs are capable of that you'll know it already because they'll have been killing other high-CR monsters like Mind Flayers and young dragons too. (Actually you'll know probably just from listening to table talk when a monster shows up--you can tell when a group is experienced at cooperative tactics. E.g. they never panic, and they may have specialized jargon.)

For a group of five bog-standard PCs with random classes and builds and played in a straightforward fashion ("I walk up to the Marilith and start swinging with my magic axe") to have a guaranteed win but not guaranteed survival for all PCs, I'd probably shoot for level 12ish, or level 15ish if they don't have magical weapons or warlock cantrips. Each PC will have to do about 40 HP of damage to the Marilith in order to kill her, which should take them 2-3 rounds if they're just attacking unimaginatively with magic weapons; meanwhile she's doing around 90 HP of damage to them per round in return plus restraining one PC. (Make the tail attack first so the longswords get advantage if it hits.) If she plays it slightly smarter (constrict the paladin while beating the wizard unconscious with swords, and then next round teleport away with the paladin to beat on him in isolation too) she might even kill two PCs.

 

[Tales and Chronicles]

I was hoping for around lvl 8, because the dungeon is more or less at the start of the adventure, if I keep it as in the game. The problem is my players are the worst strategists you've ever seen, even after multiple years of 3.X, 4th and 5th games. They still rush for the big bag, trying to be the one to get the kill (yeah...they count their kills), forget stuff on their sheets (and dont like ''simple classes'' so its a problem) and dont want to focus fire 'cause everyone want to be engaged in a fight with one enemy, sometime it feels like we're playing Mortal Kombat. Anyway, I'll probably just take the refluffed yuan-ti with her flying swords, its much more simple, it looks cool and gets the job done.

 

[Caliban]

It really depends on the characters. If you have characters set up specifically to fight fiends, they can face it much sooner than the CR suggests. If they are not, then it can be a devastating encounter even at a proper CR.

I was playing a level 12 group with 3 melee characters (Battlemaster fighter with polearm mastery and Sentinal, Wolf Barbarian w/sword and shield and Shield Mastery [he was also a werewolf], and my Vengeance Paladin 8/Tome Warlock 4 w/quarterstaff and shield and Polearm Master plus Warcaster).

The Marileth (plus supporting fiends) had six silver weapons. It chewed through the silver vulnerable barbarian in one round, and nearly killed the Battlemaster on it's second turn. My character had a higher AC than either of them and cast Protection from Evil and Good on himself then declared her his Vengeance Enemy. The Marileth only hit him once in two rounds (out of 14 attacks), and my character killed it via smites (which do extra damage against fiends and undead).

Later we met another Marileth and my character solo'd it while the rest of the group fought the other monsters in the encounter.

Against other types of creatures my character doesn't fare nearly as well, but against fiends his high AC and Protection from Evil and Good makes him a formidable opponent.

 

[CapnZapp]

More seriously: it depends entirely on the details of your party and the tactics they use. You know those better than anyone. You also know better than anyone what you mean when you say you want a "deadly" encounter. Do you mean that you definitely want to kill at least one PC? Do you just mean that you want the potential for PC death to be there if they mess up?

It's more than possible for a four-man party of level 5 PCs to kill a Marilith, but if your PCs are capable of that you'll know it already because they'll have been killing other high-CR monsters like Mind Flayers and young dragons too. (Actually you'll know probably just from listening to table talk when a monster shows up--you can tell when a group is experienced at cooperative tactics. E.g. they never panic, and they may have specialized jargon.)

For a group of five bog-standard PCs with random classes and builds and played in a straightforward fashion ("I walk up to the Marilith and start swinging with my magic axe") to have a guaranteed win but not guaranteed survival for all PCs, I'd probably shoot for level 12ish, or level 15ish if they don't have magical weapons or warlock cantrips. Each PC will have to do about 40 HP of damage to the Marilith in order to kill her, which should take them 2-3 rounds if they're just attacking unimaginatively with magic weapons; meanwhile she's doing around 90 HP of damage to them per round in return plus restraining one PC. (Make the tail attack first so the longswords get advantage if it hits.) If she plays it slightly smarter (constrict the paladin while beating the wizard unconscious with swords, and then next round teleport away with the paladin to beat on him in isolation too) she might even kill two PCs.

Anything from level 5 to level 12 sounds about right, if the goal is for the party to actually engage the demon in combat and also win that combat.

I'd peg it at level 8, myself. (I would have preferred it if the number was larger, but this is what I would say for the default game, assuming feats)

 

[CapnZapp]

I should add one thing:

A level 5 party would probably choose other approaches than combat (diplomacy, escape etc) unless they are very well acquainted with both their own capabilities and the state of monster design in 5E. By that I mean I would be surprised if even very veteran gamers would attack a Marilith at party level 5 unless they have played 5E before so they know how tough (or not) high-CR stat blocks are.

By the traditions of D&D a Marilith is not meant as a straight-up combat challenge at such a low level. The fact the 5E Marilith isn't more challenging than that is a sad circumstance, but in my opinion you should not allow this unfortunante fact to alter your perception of what a D&D Marilith represents.

 

[FormerlyHemlock]

I was hoping for around lvl 8, because the dungeon is more or less at the start of the adventure, if I keep it as in the game. The problem is my players are the worst strategists you've ever seen, even after multiple years of 3.X, 4th and 5th games. They still rush for the big bag, trying to be the one to get the kill (yeah...they count their kills), forget stuff on their sheets (and dont like ''simple classes'' so its a problem) and dont want to focus fire 'cause everyone want to be engaged in a fight with one enemy, sometime it feels like we're playing Mortal Kombat. Anyway, I'll probably just take the refluffed yuan-ti with her flying swords, its much more simple, it looks cool and gets the job done.

A quick sim (https://repl.it/EnFq/11) with very non-strategic, non-optimized characters gives me the following results:

Two 5th level Champion tanks with nonmagical longsword + shield, plus two 5th level Champion archers with nonmagical longbows, win 0 out of 100 combats against a Marilith.

If you double the number of PCs (4 5th level tanks and 4 5th level archers), they win 13 out of 100 combats.

If you bump them up to 9th level (2 9th level tanks and 2 9th level archers), they win 2 out of 100 combats.

If you bump them up to 9th level and give them all +1 magic weapons (+1 longswords and +1 longbows), they win 84 out of 100 combats, with 2.42 members still above 0 HP on average.

If you bump them up to 9th level and add another archer (2 9th level tanks and 3 9th level archers) and give them all +1 weapons, they win 100 out of 100 combats with 3.92 members still above 0 HP on average.

Code is here: https://repl.it/EnFq/11

Conclusion: if I haven't made any major mistakes, then it looks like you could do a 9th level fight with four or five PCs and get what you want, especially if you give them magic weapons.

 

[Rhenny]

I should add one thing:

A level 5 party would probably choose other approaches than combat (diplomacy, escape etc) unless they are very well acquainted with both their own capabilities and the state of monster design in 5E. By that I mean I would be surprised if even very veteran gamers would attack a Marilith at party level 5 unless they have played 5E before so they know how tough (or not) high-CR stat blocks are.

By the traditions of D&D a Marilith is not meant as a straight-up combat challenge at such a low level. The fact the 5E Marilith isn't more challenging than that is a sad circumstance, but in my opinion you should not allow this unfortunante fact to alter your perception of what a D&D Marilith represents.

Yeah, this was my reaction too.

At levels lower than 8 or 9, an encounter with a Marilith should really be just a "show me" type encounter. PCs have to bargain with it or they get lucky and something (a wayward NPC with special powers, or a magic item that they find) can help them repel it by forcing it to retreat until later, etc. Or, maybe the Marilith sticks around for a round or two, but then it gets called away, leaving behind just some lower level foes to deal with the PCs.