What would be an appropriate CR adjustment for this dragon defending her lair?

[Plane Sailing]

Arguably a dragon defending it's lair is weaker than one in the open - since it loses it's fantastic mobility which is key to a dragons survival against parties. However, lava pools are particularly good for red dragons...

In this case the dragons best bet is to grapple targets and swim under the lava with them, since the 70 average damage per found from immersion in lava will help take the fight out of them pretty quickly. He can also get full cover (+8AC and improved evasion IIRC) by swimming in the lava with just his head poking out.

So I'd probably assess this situation as especially challenging and give +50% xps if it was overcome successfully.

 

[moritheil]

Arguably a dragon defending it's lair is weaker than one in the open - since it loses it's fantastic mobility which is key to a dragons survival against parties. However, lava pools are particularly good for red dragons...

Indeed, some lairs are not very thoughtfully designed with respect to their inhabitants. I agree with you that a lava pool is a pretty good option for a red dragon, though.

 

[Squire James]

I think the main memory connected to this encounter should be "great encounter with red dragon" rather than "we got ^&$@ for XP for it".

Think of the lava lake as one big trap and come up with a CR for it. It is certainly worse than nearly all of the sample traps in the DMG, but some of the "crushing wall" traps come pretty close. I would rate it a CR 11 (given the high likelihood of the party needing to deal with it). The traps on the pillars are figured separately... I imagine these should be in the CR 6 range.

My suggestion for the "random" lava spurts is not to make them random. Put fixed locations and times for about 10 rounds of combat, and conveniently forget about them after that. Set them up like CR 7 traps (look in DMG for similar traps).

So, the survivors (if any) will get XP for the dragon itself (don't have book handy, CR 13?), a CR 11 for the trap, and several CR 6-7 for pillar traps and lava spurts. If you don't feel like doing all this figuring, assume a 100% XP bonus for all the traps, which happens to be exactly the same as +2 CR at this level range.

 

[Lobo Lurker]

Even with lava spurting up nearby, and with the stones radiating all that heat, the gold might be soft and hot to the touch, but wouldn't melt. It's all relative to the distance between the heat source and the gold.

I must say though, this would make a prime ground for some fire mephits serving the dragon. It'd activate thier fast healing.

It might be a nice place to stick in a half-dragon rhemorraz too.

Heh, or change tracks on the party and make it a half-fiendish white dragon. They'd have all thier anti-fire stuff up and get blasted by the cold.

From a realistic standpoint, being around all that lava would likely poison the players too. All sorts of scalding & unbreathable gasses.

Roll a d20 each time the pcs (singly or in groups) pass over the lava. On a 20 they get smacked by the lava (20d6).

 

[moritheil]

A lot of people are tossing about numbers. I thought that the rule for being immersed in fire was 10d6 fire damage per round. Is this wrong? Can someone point out the rules for fire and, if separate, lava?

 

[Zandel]

Lava is 2D6 if quick splash and 20D6 for full coverage
Fire is 1D6 for quick 'splash' and 10D6 for full coverage

Please remember that a dragons CR assumes that the party knows about and has fully prepared to face this dragon and it's defences. Throwing them a curve ball with a dragon can quickly lead to TPK's.....not that I have a problem with that.

 

[moritheil]

Lava is 2D6 if quick splash and 20D6 for full coverage
Fire is 1D6 for quick 'splash' and 10D6 for full coverage

Please remember that a dragons CR assumes that the party knows about and has fully prepared to face this dragon and it's defences. Throwing them a curve ball with a dragon can quickly lead to TPK's.....not that I have a problem with that.

Where does this come from? Sorry to bother you, but I've already seen the numbers above, and what I meant to ask for was a specific quote or page reference.

Thanks!

 

[Zandel]

DMG I think.....can't remember....haven't had to look it up for very long time...

 

[moritheil]

DMG I think.....can't remember....haven't had to look it up for very long time...

It's as I feared. Truthfully, I regularly use the 10d6 fire, and just want the reference for the 20d6 lava. Thanks anyway!

 

[shilsen]

It's as I feared. Truthfully, I regularly use the 10d6 fire, and just want the reference for the 20d6 lava. Thanks anyway!

It's on pg. 204 of the DMG under "Lava effects"