How to make the battle against Tiamat last longer?

Question

I am running Rise of Tiamat and the party (2 barbarians, 1 fighter, 1 paladin, 1 druid, all level 15) is going to fight Tiamat in a few sessions. I'm particularly concerned not only about the balance of the encounter, but also about the duration. Both sides have a huge damage output per round, with the party having more than 10 attacks and Tiamat having 2 breath weapons and three attacks. The fight may end in a few rounds and this is bad for two reasons: 1) it's not fun and 2) the final outcome depends on a few lucky/unlucky shots.

I want to make the battle last longer without breaking the balance. The first approach would be to increase the HP and decrease the damage. The second would be to add some minions that keep the PCs busy without inflicting too much damage. What could be the most secure solution?

Answer 1

Deny the characters a melee

If your characters are typical, the two barbarians and the paladin are built for melee. Facing them, Tiamat (Intelligence and Wisdom both 26) should absolutely avoid melee. Your 15th level druid has all of two spells (one 7th, one 8th) that can affect Tiamat directly, with her Limited Magic Immunity. That leaves the fighter as their only ranged attacker, and only if they have a good ranged weapon, like a longbow and multiple arrows of dragon slaying.

Tiamat regenerates 30 hp per turn, unlimited, for the duration of the fight. Her breath weapons have unlimited uses and no recharge. Your characters have limited healing resources. The longer the fight goes on, the more likely Tiamat will win, and she knows this.

Yes, a claw / claw / tail combination followed by Bite legendary can be a big bucket of damage, but it makes her too vulnerable to character attacks. Tiamat should never end her turn closer than 80' to the PCs, or whatever she judges their dash move to be. She should use her fly speed of 120' to keep her distance. She will also very seldom be using main actions; her legendary actions are enough unless for some reason the party is protected against every kind of energy attack (she might occasionally need to use her Frightful Presence if too many of them have fly speeds). Typically she should fly to within breathing distance of the party, ready an action to move away from them if they get too close, and then wait for their turns to breathe using her legendary actions. This might include flying directly above them but still staying 80 feet or more away - at 90 feet directly over them, her Red Dragon Head makes a 90 foot diameter circle of damage at ground level.

Run this way, it can be a very tactical, satisfying boss fight over many rounds as your players try to maneuver her into melee and she tries to kite all five of them at once.

I have had one party that fought Tiamat, and they did so three times. The first time was in the Well of Dragons Temple at the conclusion of Rise of Tiamat. There they had to eliminate the red wizards and end the ceremony before she could fully manifest on the Prime - the longer the ceremony went on, the more Tiamat emerged from the well, one head at a time. They ended the ceremony with just three of her heads present. The second time they fought the Aspect of Tiamat from Fizzban's in an ancient roofless temple where she was able to make full use of her fly speed by moving directly over the temple and then retreating. The third time was in her prison-cave on Avernus, where the fight was 'for real'. Of the three, the second fight was definately the most difficult for the party, and the longest, simply because the open sky gave her so much mobility. Your choice of setting will very much determine the length of the fight by dictating how easy or difficult it will be for the characters to force her into melee.

Answer 2

Consider Phases or Secondary Objectives over Buffs

DnD is ultimately a very difficult game to draw out, because certain spells and abilities are so impactful. You could add minions, but one well placed area of effect spell could wipe them. You could increase HP, but the big bad can still fail a save and may just lead to them taking an extra round or two of uneventful damage while stunned.

One of the most effective ways to draw out an encounter, in my opinion, is to add complications. Some examples:

• There are hostages in the lair. Freeing them might increase the reward after the encounter.

• The lair is waking up. Barricade the doors to stop wretched creatures from overwhelming the encounter.

This all adds complexity as a DM, and you're welcome to run an encounter in whatever way is most fun for you, but the most reliable way I've found to not insta-kill your big bad is to give the players something more pressing to spend their actions on.

Answer 3

Don't treat Monsters as Monsters - they don't know their own stats!

Monsters are beings you should be roleplaying. Including Tiamat.

Tiamat doesn't know her exact HPs, nor the damage output of the PCs. She will be confident that "mere mortals" can't hurt her ... until they do.

The "Bloodied" condition (half max HP) can be the point where a blow goes from being shrugged off, to actually connecting and causing damage.

So from Tiamat's perspective, the fight consists of the PCs ineffectively throwing attacks at her as she smashes them. They, surprisingly, aren't smashed instantly - in 99.9% of Tiamat's interactions with mere mortals, each attack turns the target into a fine mist. Here, she is fighting mortals who don't evaporate.

It is concerning.

Then they bloody her. Whichever attack breaks 50% HP is akin to someone being in a bar brawl - knocking heads, dominating as usual - then suddenly they are stabbed by a knife. It isn't a deep wound, but it actually hurts and it means that the fight isn't going the way you expected.

Retreat and Regroup

Engage the PCs before they reach the "final objective", whatever it is. If they are trying to get a macguffen, fight the PCs outside the structure where it is. Have some tactical depth to the situation, and make the first engagement a bit of a "Tiamat's choice".

Then, when things go poorly (she is bloodied), Tiamat will disengage. Her speed is pretty fast, so the PCs will only get a few blows in as she leaves. Any mobility the PCs have - cloaks of the monteback, boots of speed, etc - may let them stay in range for an extra turn, but will probably cost them some offence.

Once out of range, Tiamat rapidly heals to full. She'll call in any support she has. Odds are the PCs are trying to threaten something Tiamat values (maybe a location?), so Tiamat will fall back to guard that.

The second fight kicks off against a full HP Tiamat who is now going to avoid closing in melee. At the same time, the PCs have an objective - destroy an anchor? Trash her thone? - that compels Tiamat to actually stop the PCs.

At the very least, this has increased the length of the encounter by 50%. And if you add in some harrying of the group as they advance...

She is still an arrogant god

I'd maybe lean into the multi-headed thing for roleplaying her.

• Red: Vengeance, Wrath
• White: Beastial
• Black: Sadist
• Blue: Pride
• Green: Scheming

Blue will object to treating mortals as a real threat. Black will enjoy torturing the PCs. White will probably be the one who reacts to the damage and gets her to flee, which Blue will treat as an affront. Green will try to manipulate the other heads.

Red, however, is dominant. And after the PCs "win" round 1 by bloodying her, will want to completely destroy them.

In the first fight, white gets wounded. In pain, Tiamat flees. Blue objects strongly. Red promises retribution.

In the intermediate part, Black laughs as she tortures the PC with breath weapon attacks from afar and cover. White continues to nurse her wounds. Green teases Blue.

In the second fight, they start at range, and pepper the PCs with breath weapons and the like. Blue insists they close range and kill them. White objects. Green teases Red. Red smacks White down and Tiamat charges into melee after 1-2 rounds.

Answer 4

Divide the fight into phases, each with a different form of the boss

This answer contains spoilers for Rime of the Frostmaiden campaign.

Note: This does increase the work you need to do as a DM to prepare the fight as you need to homebrew/find/adapt the stats and descriptions for different forms but if you’re comfortable fiddling with HPs, damage outputs and other monster stats, this might be something you could pull off and enjoy.

The thing about prolonged combat is that there is a high chance of it becoming repetitive and boring after a few rounds - you keep hitting the same thing over and over again, the thing keeps hitting you with the same bunch of attacks round after round and you’re just waiting for the point where you have hit it enough that it dies. I’ve taken part in combats like this as a player and I’ve made the mistake of creating a few such combats as a DM, too. This is basically what you get if you increase HP and reduce damage output of the monster.

Instead of making the party keep fighting the same monster for 10 rounds (or however many you want), create different phases of the fight, with the monster taking on a different form in each phase. Rime of the Frostmaiden is a campaign that handles the final boss fight like this and when I ran it, all players agreed that it was really cool and exciting even though the fight took over 2h in real time and it was with the single opponent. The final boss has 3 distinct forms, and each one comes with a separate stat block, description and image. Once the party brings the first form down, the creature transforms into the second one and so on, only after they beat all 3 is the fight over. Each form has different attacks, strengths, weaknesses and so on, this solves the problem of repetitiveness, adds some uncertainty (“how many more times is it going to transform? Do we unload everything now or save the strongest stuff for later?”) and you can throw the players a curveball by having the boss stand back up again meaner and stronger just as they were patting each other on the backs and making comments on how easy this was.

Answer 5

Tiamat's Fighting Withdrawal--Corners, Traps, Dividing the Party

Put Tiamat in a cavern system with lots of twisting tunnels and chambers that vary in size from very narrow to vary large. Tiamat knows the layout of the cavern system, but the PCs do not. Tiamat uses this to her advantage. She hides around corners to prevent direct-fire, ranged attacks. She flies in large caverns to avoid close quarters melee. She circles around behind the party or pops out of a secret door to surprise attack. She uses traps that divide the party: shifting doors and walls, deep pit traps, falling portcullises, etc. Then picks them off one at a time, weakest first. Portions of the cavern system will flood with water, fire, poison, acid, boulders, etc., as she pulls levers to trigger traps, etc. She retreats, [trap], retreats, [attacks from unexpected direction], retreats, [trap], etc. She uses fighting withdrawal to wear the party down. Draw them deeper and deeper. Then, she circles around and blocks the only escape route. Victory or death. :-)