Harzel
Adventurer
I'm envisioning a situation in my PotA campaign session tonight where the PCs are talking to Shoalar Quanderil in the Womford Rats encounter. I've kind of decided that Shoalar will probably get bored of the conversation quite quickly and will cast Tidal Wave at the PCs standing on the dockside.
I'm just wondering how to handle it - I know there's no 'surprise' because they all know each other are there, but I don't really want to open the conversation by saying we roll for initiative, because that hints that combat is imminent.
Should I say something like, "He starts to mutter an incantation", and give the PCs a chance to have a reaction? Perhaps the save that they get against Tidal Wave is their chance to react. And from that point, we roll for initiative.
I want to be fair.. I'm not one of those DMs who seeks to kill the party in every battle.![]()
I think others have posted a variety of good answers. I will just add that I would take the PCs' attitude (as evinced by their statements or declared actions) into account. If they are extremely wary/suspicious, I would just narrate the NPC starting to act, then roll initiative; if they are somewhat wary, give them advantage on an insight check (vs NPC deception if he's trying, or a low DC if not) for being surprised; if they are blase, then they make the check straight.
On a different front, I know you didn't ask for advice on this but this was the first thing that popped into my head when reading the OP. I don't have PotA, so I don't know the NPC or his motivations, and I don't know what your PCs know about him. That said, it seems like you might be steering things toward one particular outcome before knowing what the PCs do. Preparing for a likely course of events is wise; deciding in advance that is what is going to happen unconditionally, not so much, IMO. But then, I might be assigning you thoughts that you didn't have, in which case, ignore this and carry on.