The weirdest party wipe happened two days ago

[Particle_Man]

I too am curious as to where you go from here, in-game (if this campaign continues somehow) or if you start anew, perhaps with a “session zero” discussion with the group.

[noce]

probably bad strategy on part of other players too; a coup de grace is a full round action that can be interrupted a number of ways, the party could have defended their incapacitated member. also, I don't know how common magic items are in your campaign, i do expect a fighter to cover his most blatant weaknesses by level 12

Not only this, but a coup de grace means death only if the victim fails a Fort save (10 + damage): a giant Psurlon critical hit is 23 on average, so DC 33 Fort save without DR (it drops to DC 30 even with a pity lesser crystal for just 2000 gp).
I would assume a multiclass lvl 12 fighter to have at least 17-18 Fort save, based on level split and magic items.
I would also assume a way to reroll saves by level 12.
So, succumbing to a coup de grace is not something I would take for granted in such a situation, unless the fighter is badly equipped.

On top on that, Third Eye Freedom is just 2600 gp.

[Jon_Dahl]

Not only this, but a coup de grace means death only if the victim fails a Fort save (10 + damage): a giant Psurlon critical hit is 23 on average, so DC 33 Fort save without DR (it drops to DC 30 even with a pity lesser crystal for just 2000 gp).
I would assume a multiclass lvl 12 fighter to have at least 17-18 Fort save, based on level split and magic items.
I would also assume a way to reroll saves by level 12.
So, succumbing to a coup de grace is not something I would take for granted in such a situation, unless the fighter is badly equipped.

On top on that, Third Eye Freedom is just 2600 gp.

The CdG damage was just measly 12 points. I do not remember why the damage was so low, but maybe it was a bite. Hence, the DC 22 fort save that was failed.

[Remuko]

I don't think we discussed that, but it took more than one day.

then that's just weird. he had multiple days to prepare spells that would be useful here, or even just a teleport to get him where he needed to go, after getting back from Sigil. very very odd play from the caster.

[icefractal]

A lot of GMs do enter shortcut mode in situations like this, where the point is to get the other players back in action ASAP. In that mode, the question is just whether you have a way to resurrect them and are willing to pay the cost. So no encounters will happen unless really forced, and the player of the surviving PC is expected to act expeditiously (in real time) and not spend time on unnecessary precautions or side matters.

So if the player in question isn't familiar with your GM style, this seems like a natural mistake. You're thinking of the return from Sigil as "a challenge they should approach as seriously as any other" and they're thinking of it as "something to skim through so we can all be playing again"

[Jon_Dahl]

A lot of GMs do enter shortcut mode in situations like this, where the point is to get the other players back in action ASAP. In that mode, the question is just whether you have a way to resurrect them and are willing to pay the cost. So no encounters will happen unless really forced, and the player of the surviving PC is expected to act expeditiously (in real time) and not spend time on unnecessary precautions or side matters.

So if the player in question isn't familiar with your GM style, this seems like a natural mistake. You're thinking of the return from Sigil as "a challenge they should approach as seriously as any other" and they're thinking of it as "something to skim through so we can all be playing again"

Yes, but the other players were already half done creating new characters, and the player of MT knew this.

[Particle_Man]

Oh that changes things. Maybe the MT player wanted to make a new character to start fresh with the other two new characters?

[Coeruleum]

From an outside POV, this looks more like an attempt to kill your party. But maybe they like living dangerously.

I'm not familiar with Psurlons, and there seem to be several at several different CRs, so I'd need to know which you were using to make any statement on the balance of the encounter, but generally...

Hold Monster is a will save, 9/10 times it's going to completely screw any non-caster.

Coup de grace is almost always a move I avoid without very explicit reason to do so or desire from the player.

I roll a Percentile for accuracy with all teleporting, but it is reduced with caster level, and only goes up to 100 miles off. But this reads an awful lot like "Player is trying to help their friends, the DM is doing everything they can to keep them from getting back." I don't understand why the Mystic could Plane Shift back....but not teleport from the island to his hometown?

I have no real problem with enemies playing smart. But this "series of unfortunate events" looks a bit sus from the outside. Maybe I'm overly generous with my players.

Yes. Especially since there are lots of ways of raising the dead without diamonds, and the PC just didn't pick any of those. Lowering the availability of diamonds doesn't make it super harder to resurrect PCs, it just makes it harder for that particular character. I don't even want to tell OP about these things because then OP will just nerf other kinds of characters into oblivion too, or even ban them. Heck, OP probably told their players what to play. I've done lots of theurging but never the actual mystic theurge class because it's never seemed that good to me, and in a world where you can't actually get materials for arcane or divine spells easily, it seems much worse than it seems in worlds where you have plenty of materials available compared to this one. Arcane Hierophant is probably a better theurge class for arcane/divine than straight Mystic Theurge regardless of resources. In a limited-resources world, I'd be inclined to go Mind Mage, Noctumancer, Soul Manifester, Soulcaster, Anima Mage, Eldritch Theurge, Jade Phoenix Mage, or basically anything else that at least gives me one option that isn't dependent on gold, expensive materials, and expensive focuses to use, though. Mystic Theurge feels like the epitome of wallet-casting and doesn't even give you class features like Arcane Hierophant does. Arcane Hierophant is better than Mystic Theurge for the same reason Mind Mage is better than Cerebremancer (but you might need some levels of both to round out your progression.)