D&D 5E Understanding Adult Red Dragon

[S'mon]

Tactically, it wants to use Wing Buffet early on to knock PCs prone, before it does FP & claw/claw/bite.

Flight - depends on how easily you let dragons take off. I don't treat them like hummingbirds, but they like to have lairs with steep cliffs and other easy ways to get airborne.

Fire Breath - pretty good either as opening gambit (to get everyone hurting, maybe even at 0 hp) or for second round since Frightful Presence + CCB is a nice opener, but FB can't be reused vs PCs who save. Generally if the dragon starts airborne then Flame is best; if it is caught on the ground FB-CCB works well.

I would generally expect an adult red to trash a level 7 party, especially if it uses its multiattack routine to finish off fallen foes with a couple CDGs.

Re spellcasting, a good spell selection can greatly increase threat; Shield in particular is extremely effective. A minmaxed CR 10 Young Red with spells can be quite a threat to level 7 PCs.

Lair Actions - I tend to create my own, and give Ancient dragons much more powerful LAs than the ones in the book. Obviously you only get LAs in your lair, and they compensate for the restricted space.

 

[S'mon]

That's fair enough. I don't think that variant rule specifies that it is an action to use a spell but I would guess so.

Yes, so bonus action and reaction spells are particularly nasty for a dragon.
I did give ancient blue Cadrilkasta 'animate objects' as a bonus action in my Shattered Star campaign, but in-universe that was a result of her having the Shard of Sloth, a powerful artifact.

 

[S'mon]

Of course it is, but given the dragon especially a dragon of this caliber is noting the party approaching he will use it before any combat has started, at least that is how I do handle it on my table. Do not complain that it is out of initiative or so, because the other way would be a surprise attack by the dragon.

Plenty of PCs can't be Surprised (Alertness) or can act while Surprised (Barbarian), and PCs often have great Stealth & Perception, so this isn't some kind of favour you're doing the PCs.

IMC I'd certainly roll init first, dragons have great Perception but not Stealth so it's rare they surprise PCs IME. And the dragon would use FP on its first turn as per RAW.

 

[S'mon]

If I recall, Cirothe's lair has a lake of lava. Since she's immune to fire damage, she could plausibly pop in and out of the lake, black-dragon-style. This would let her pop up, breathe fire, pop back down, behind total cover of lava, all in a single round. The only way for PCs to affect her would be readied actions, which limits them considerably (no multiattack, insane rules for readying spells, etc.).

This is fantasy lava, ie it resembles water not liquid rock, then?

 

[Oofta]

This is fantasy lava, ie it resembles water not liquid rock, then?

I was going to say the same thing. Lava is far denser than most people realize.

From an article at Wired magazine (limited hits per month so here's the relevant part)

Molten lava is nothing like water. Sure, everyone thinks that liquid rock (magma) is going to behave like any other liquid (e.g., water), but there are some key physical properties that tell us it just isn't the case. Let's compare!​

• Water has a density of 1000 kg/m3 and a viscosity of 0.00089 Pa*s.​
• Lava has a density of 3100 kg/m3 and a viscosity of 100-1000 Pa*s.​

Pa*s is the SI unit for viscosity – some people might be familiar with other viscosity measures like poise. Viscosity is, more or less, the resistance to flow, so if you throw something in a liquid, a low viscosity liquid (like water) will "get out the way" and you'll sink faster relative to a high viscosity liquid (like cold corn syrup). The density of the liquid will also play a role in how quickly you might sink based on your own density. So, when we're looking at water versus lava, lava is ~3.1 times the density and between ~100,000 to 1,100,000 times the viscosity. They are very different!​

​

 

[MarkB]

To be fair, if it's not fantasy lava the PCs will be cooked before they even enter the lair.

 

[S'mon]

To be fair, if it's not fantasy lava the PCs will be cooked before they even enter the lair.

People go walking on lava IRL! So I'd think some fire resistance and/or scads of hp would cover that. I would probably say something like 5 damage/round in enclosed space though, similar to being adjacent to a Fire Elemental - will cook Commoners right away.

 

[MarkB]

People go walking on lava IRL!

Cite please? As I understand it, even standing close to molten lava will expose you to temperatures that will ignite clothing and even flesh. You can do it, but only in an asbestos suit with active cooling systems.

And putting it in an enclosed space like a lair would essentially turn that entire space into one big smelting furnace.

 

[Oofta]

Cite please? As I understand it, even standing close to molten lava will expose you to temperatures that will ignite clothing and even flesh. You can do it, but only in an asbestos suit with active cooling systems.

And putting it in an enclosed space like a lair would essentially turn that entire space into one big smelting furnace.

Click here to see an article which has a video of a guy running across lava.

 

[Coroc]

Click here to see an article which has a video of a guy running across lava.

Which is a trick, in keeping the exposure very short, it's like jumping through the harvest fire or walking on glowing coal with bare feet. What is correct though, is that you will not sink in like with water. Maybe you and @MarkB have different lava temperatures in mind.
While a lava stream pretty much downhill of a volcano might cooled of enough be crossable with minor burns if you are fast, @MarkB is correct on Lava e.g. directly in active volcano which you wont survive even by standing only close enough to it because it does heat up the surrounding air to much.