Saeviomagy
Adventurer
Diety arrives and sings the "heart in a box" song?
I've had GMs use "Last week on D&D..." pre-session recaps (like non-episodic television shows often have) to good effect. This not only allowed them to refresh their players' memories of what happened in the previous session and what direction the session was heading but it allowed them to highlight story elements that were missed or glossed over. If the session recap notes that the burned body at the funeral was amiss it could encourage the players to re investigate it.
Another technique is to have the players do the pre-session recap. This way you get insight into what the players took from the previous session. If they gloss over the burned body during their recap and it's pivotal for your campaign, you know you have to give them additional clues and/or more obvious clues.
These pre-session recaps might not help in this situation since the game is so close to its end. But if used throughout the campaign they may have cut the issue off at the pass.
Op back again - so next week is the week it happens. The party have made their way up the tower where the BigBad is at the top - they are one floor from the top, ready to head up. And here is what I have decided...
I am going to late fate decide (cowards way out), but also give them a chance. The rules of the game were simple - Discover who the big bad (done), discover they had created their horcrux (taken out their heart) (done), discover where the heart was (missed), destroy the heart (missed), confront and kill the big bad (on Monday).
So what would happen when the heart is not destroyed? Making the BigBad invincible is too set in stone. But they did miss the obvious (and all their comments tell me they were close, but the one who got close was generally hushed up by somebody who 'wanted to go shopping'), so it has to be tough. So heres how the fates will play it out....
The battle will start, and every time its the big bad has a turn, they will heal - their wounds would close up, blood wound sink back into their body, burns would disappear (and they will heal for 3d8+4). So getout #1 is that they can destroy the bigbad if they can really damage it. Getout #2 is they recognise what is happening.... and just run away.
I am also going to put a teleport mirror in the room - it kind of makes sense the bigbad would have a method of getting to their sect HQ where the heart is stored - so if they want, their get out is to teleport to the sect HQ and kill the heart. I will make it obvious when they enter the top of the tower that this mirror has no reflection but a special shimmery quality to it. Knowing my (hack, slash, ask questions later/never) group, they will probably ignore it.
But, also, at the start of every round, I will roll a D20 - on the 2nd roll of a 20 (this will be a long battle, 1/20 odds is too easy, I want 1 in 40), the inn keeper will appear at the top of the stairs, arrows in his back, bleeding to death, cloth bag soaked in blood in his hand, and inside the bag will be the heart. If they help him, he will gasp "found heart" and die (on his body will be the maps of how he found the heart) - if they destroy the heart, then battle comes to its natural end (they win, or they lose).
And finally - I wont let it be a TPK. If they all start to die, When it gets down to the last 2, the BB will shout 'surrender' and will imprision the remaining 2 in her basement cells (I had already placed an entrance to this in the ground floor of the tower ready for this before they came into the tower... just in case) for the rest of their lives, to work as slaves.
So that's my decision. It all makes sense in terms of story line, and the fates of the dice and the PCs actions will decide how it all plays out. It may be an (almost) TPK, or they may just go hammer and tong and kill the BB or they may run away - I have no idea how this will play out... but I have given them lots of fighting chances.
I am also going to put a teleport mirror in the room - it kind of makes sense the bigbad would have a method of getting to their sect HQ where the heart is stored - so if they want, their get out is to teleport to the sect HQ and kill the heart. I will make it obvious when they enter the top of the tower that this mirror has no reflection but a special shimmery quality to it. Knowing my (hack, slash, ask questions later/never) group, they will probably ignore it.
And finally - I wont let it be a TPK. If they all start to die, When it gets down to the last 2, the BB will shout 'surrender' and will imprision the remaining 2 in her basement cells (I had already placed an entrance to this in the ground floor of the tower ready for this before they came into the tower... just in case) for the rest of their lives, to work as slaves.