Monster Advancement: upping CRs?

[Taloras]

Im just curious. I cant find my DMG, so i was looking at the monster advancement in the MM. It says you dont up the CR for a creature no matter how much you up the HD. So if i take a Kraken(20HD), and up it to max (60HD), its still a CR12 encounter? I understand they get 3 times the XP, but id say thats a lot harder than a CR 12 encounter. im talking 290 HP vs 990 HP. Better saves, better attacks.....thats definitely not a CR 12. So how do you change CR w/ Hit Dice?

 

[Seravin]

Page 102 of the DMG. Tougher Monsters
In essence: a 50% increase in HD raises the CR by +1. Doubling the HD raises it by +2.

The Monster Manual II has a better example in their side bar.

The example in the Monster Manual says the CR doesn't raise, but by doubling the experience points gained you effectively added two to the CR (looking it up on the experience point chart in the DMG anyways)

 

[dcollins]

Im just curious. I cant find my DMG, so i was looking at the monster advancement in the MM. It says you dont up the CR for a creature no matter how much you up the HD.

This was changed in MM errata to match the DMG rule.
CR officially increases by +1 per +50% HD.

 

[Taloras]

Ah. thanks. I dont have my DMG anymore (gotta talk to some friends.....)

I was just trying to figure out. Im working on an undersea campaign....i was thinking of throwing a 60 HD Kraken at em....that would be CR 16, right? they start out at 20 HD CR 12...

 

[Celebrim]

From personal experience a flat +1/50% of HD doesn't always work. For instance I tend to add an 1 CR per size increase, as a size increase is in itself a major advantage actually independent of (but related too on the advancement table) increase in HD. That extra HD that bumps the creature up from medium to large involves a big jump in CON and STR, as well as increased reach, and is thus alot more important than a HD increase that doesn't. Also, things tend to get wonky when you add templates to advanced creatures because advanced creatures of a given HD tend to be odd in thier design compared to similar HD creatures of a given fixed CR (they often lack the defences of a normally high CR monster), and a little fudging may be necessary to get a reasonable figure.

'Savaged Species' I think has a more up to date rule, but I don't know the details.

 

[Taloras]

Hmmm...im just trying to get a decent end monster for the campaign im workin on. I think a CR 16-17 aint that hard. Maybe add even more HD on there(past the norm...this is gonna be one tough Kraken)