D&D 5E Help balancing plot

[randrak]

Greetings,

I'm planning a major plot for my party which is integral to the personal plot of one of them. The plot involves several uses of creatures from the Elemental Plane of Air as the big bad is basically trying to break free from it. The Party is composed of a Battlerager Barbarian, an Eldritch Knight, a Hunting Ranger and the PC most involved, the Storm Sorcerer. All of them are at 8th level, they are a very high damage team, though very few heals. We also use an adapted injury system from the DMG (when a character drops to 0, they gain an injury).

The plot's encounters start simple:

It first involves a chase after an Assassin (CR 8, Medium Challenge) after he completes the kill. They would have to run through a large castle all the way to the top as he tries to escape. Along the way they will encounter a group of 2 Veterans and 1 Knight (3xCR 3, Medium Challenge) and later a group of 4 Cult Fanatics (4xCR 2, Medium Challenge), the first of which can be avoided if they sneak (though I doubt they will, knowing my party).
The party will arrive as the antagonists are released from their prison in another plane, a level 14 Storm Sorcerer and a level 14 Tempest Cleric. They are not supposed to fight the antagonists as they will release a few minions from the elemental plane and attempt to escape while the party is busy. The minions released will be a CR 7 and 2xCR 1/4 (Hard Challenge), though it will be in close quarters as the CR7 will be unable to fly. The antagonists try to teleport away, hopefully the party will know better than to stop them and force them into the battle. As they leave, the party is informed of their plan to release their master by completing an old ritual and that will be completed shortly (7 hours or so). After the young dragon is defeated, the party would bare witness to the ritual. They will be atop the highest tower in the castle and will see that several villages around the area are being attacked by monsters. To stop the ritual, all monsters will have to be destroyed or otherwise made to leave the area.

The villages are one hour apart by horse (they will be able to get horses if they remember to do so).
- One village will be attacked by a CR 9, Medium Challenge;
- One village will be attacked by a 12xCR 1/2, Medium Challenge;
- One village will be attacked by a CR 8, Medium Challenge;
- One village will be attacked by a 2xCR 5, Medium Challenge;
- One village will be attacked by a CR 6, Easy Challenge, however this one is permanently invisible and they lack any way of discovering an invisible enemy;

Another way to stop the ritual is by finding the antagonists who will be hidden somewhere in the large area. The further the ritual progresses, the easier it'll be to find them if the party is smart enough.

If they are unable to stop the ritual, they will release a CR 14 (Deadly Challenge). While the boss will then proceed to destroy the area, it will then leave if not attacked as it cares little for the party (and then further the plot for later on). If attacked, it will display his might but will not chase them if they flee.
If they can stop the ritual, then the antagonists (Sorcerer and Cleric) will appear and try to kidnap the party's Storm Sorcerer for plot related reasons. They are only interested in kidnapping the Sorcerer and will not pursue if the rest escapes or kill if they are knocked unconscious, unless forced to do so. If they drop to about half HP, they will try to flee through teleportation once again.

I still don't know about what rewards I should give, but I'm more worried about balance. I don't know if this is too much for the party in terms of challenges and the time constraints. What do you guys think?

 

[Ancalagon]

You need to give us more background here. This castle they are going through, is it hostile to the PC, is it the home of the assassination victim etc?

 

[randrak]

You need to give us more background here. This castle they are going through, is it hostile to the PC, is it the home of the assassination victim etc?

The castle is home to the assassination victim. The party is invited there and the assassin works for the victim, but stabs him in the back. The assassin also managed to turn several people in the castle to his side, meaning that a large portion of the castle will indeed turn hostile to the players.

 

[randrak]

Anyone? :|

 

[Jediking]

You seem to have given enough thought to the NPCs and boss and what they will do if they are losing/knocked around. Do the same for the PCs. It seems like a really fun session to run, and there are lots of little ways you can adjust it that already have in there. If they are seriously flagging part way through and you don't want them to fail (and ask how willing are you to let them fail/die), some enemies might have hidden consumables that recharge spell slots or HP. Maybe they can take a short rest without the hour requirement.

If they face every encounter, it looks really tough. Especially if they don't realize how tough the final encounter will be and spend too many resources early. But that's the format for an adventuring day. Even telling them before the session that it will be a doozy might get them to try a different tactic that usual.

And the biggest threat isn't the CR of a creature, it's how a DM uses it. A low level party can kill a dragon that sits there and swipes at them, or die before setting foot in it's lair. If the Assassin finishes off a downed PC, that's a lot different than letting him get healed even with an injury. Your tactics will make the encounters more or less challenging, so you have some measure of control yourself.

 

[randrak]

I actually make short rests last half an hour rather than a full hour.

My party has a tendency of going nova early on, might be a side-effect of my rarely giving them long adventuring days but I can definitely warn them that this plot is long and they should be more careful.
I like the idea of adding in consumables if I see them being too battered early-on. They also have an item that they can use to request the help of a level 12 Abjuration Wizard friend of theirs, though they will need to pass some checks to be able to use it.

 

[Ancalagon]

I think your challenges will be more pacing and managing information than anything else. Your little extra info makes the OP make a lot more sense. This has the potential to be a very engaging scenario (well done) but a few pitfalls may frustrate the players and sour the experience a bit.

The assassination: This should be foreshadowed with the lightest of touch. You don't want the party engaged in a "save the important NPC" quest while you "have" to kill the target for the plot to work, making their effort an auto failure, which is always frustrating. Consider options - what if the players *do* stop the assassination? Perhaps the target survive but is incapacitated by a poison.

The other castle dwellers: I can see how some may have been turned, or may believe that the party is responsible for the assassination. You will need to give enough information to the party so they know they have to rush after the assassin, not try to talk everyone out of being angry at them.

They will be atop the highest tower in the castle and will see that several villages around the area are being attacked by monsters. To stop the ritual, all monsters will have to be destroyed or otherwise made to leave the area.

This part is a bit... peculiar to me, almost forced. I'm not saying it's bad, but it's not something that makes intuitive sense. What are these monsters doing, conducting sacrifices? Monsters rampaging is a peculiar ritual. Again, proper information will have to be given thought, so the party knows what to do or at least has enough clues to piece it together.

One of the thing that troubles me a bit about this series of events is the speed at which things are unfolding. So these two powerful NPCs are imprisoned, and as *soon* as the assassin breaks them out they trigger a ritual that covers several villages? Imagine someone breaking out of prison and 5 minutes later carrying out a complex bank heist... it's a bit much.

 

[randrak]

A little more information: The assassination victim is one of the party member's grandfather who has been thought to be evil based on the way that party member was raised. In truth he sheltered her far too much out of fear for her becoming like her parents. The party will be invited into the grandfather's castle where he will inform her that he had been keeping a seal active for decades that imprisons her parents in the elemental plane of air, because they were at the time trying to unleash a big evil from that plane into the material plane. The grandfather is on his deathbed (from old age) and wishes to pass on the key that keeps her parents locked up to her since he won't be able to continue. Once he is killed (his heart only needs to stop for the seal to be broken) the seal is broken and antagonists begin opening a portal to the material plane.

Some of the people in the castle were loyal to the son and not the grandfather. They had been waiting for the perfect chance to kill the old man and capture their master's daughter (party member). Once the assassination takes place, the loyalists will start slaughtering the rest of the personnel in the castle. The party will see signs to this massacre as they chase after the assassin and will be see loyalists actively killing other castle staff.

The ritual that the party needs to stop had been started and interrupted decades ago with all the preparations having been finished already. The moment the antagonists break free, a number of evil creatures (followers of the big bad) will be released as well and rush toward their locations. The one staying back will be instructed by the antagonists to capture their daughter if possible, before they leave. The rest of the beings attacking the villages aren't doing it randomly because they need a large amount of sacrifices for the ritual to work. As such, stopping the creatures from killing people will stop the ritual. The antagonists will be hidden in a secret location where all the souls of the dead will be gathered.
The antagonists wish to rush the ritual and free their master because they had been preparing for it for decades while stuck in the Air Elemental Plane. The need to release their master is even greater since this master is very impatient and wishes to be free as well.