How do monsters roll DEFENSE?

question
#1

Our mage cast the basic magic Lightning Bolt, which requires the targets to roll DEFENSE. Our GM winged it by using the caster’s roll as the target, which worked well.

But I was curious what the rules say on it, and based on skimming over the the ME, it seems like roll DEFENSE is always discussed in the context of the players. The big unanswered question seems to be "what is the challenge rating of the PC (or PCs)?

The challenge rating for the room doesn’t make sense, given we have all kinds of examples that imply that rating is for the PCs, such as a tougher monster showing up or leaving increasing or reducing the target number the PCs need to meet or exceed. So it’s pretty clear that target number is for the PCs.

Using the actual attack roll really does seem like a good way to handle this, but I was curious what others have done in the past?

Using Monster Defense
#2

Use their CON, arbitrate if they should have extra protection from armor/magic/etc

#3

I’d take the monster’s defense to be their CON + 10 and roll that against the caster’s INT + 10.
Since there is no roll to be made on the mage’s side, that seems to be the most straightforward solution.
If you wanted the mage to roll to cast lightning bolt, you could make it an opposing roll (mage rolls d20+INT and enemies in a straight line affected by lightning bolt roll d20+CON; whoever rolls highest wins).

#4

I couldn’t tell you where, but I think I remember hearing that enemies always roll on the room target UNLESS they are attacking a PC. I remember having this question a while back when looking at things like the Snake Man’s Healing Touch.

Enemies rolling on the room target might make a spell like Lightning Bolt feel a little underpowered. Or it could make for an interesting dynamic in which you’d prefer to only cast it in higher-target areas. Idunno. I’d have to play with it.

It also seems totally reasonable to set the target as the caster’s INT+10.

I’m gonna dive into Hankerin’s ICRPG mechanics videos and see if I can find where he mentions this. If I find it I’ll reply with a link.

#5

When an Enemy rolls, they roll d20 plus any modifier they have against Room Target (Hard / Easy as appropriate).

If the enemy has a +X Stats or +X All Rolls, use that. No enemies in recent editions have a CON specific Stat listed, nor DEF, as that’s newer too.

That said, I tend to build some nemesis and boss level custom enemies with a specific DEF or SAVES stat so they are tougher without being straight up immune to a long list of stuff.

#6

Yep. I would either:

  • Have the enemy roll their bonus against the room target; or

  • Use a competing roll.

#7

Thanks, this has been a big help! We had a lot of confusion because monster’s have different stat blocks. Sounds like we did okay since we ended up doing a type of competitive roll. But it’s good to know the ways the rules intend, just to help with any future confusion.

#8

I do this as well, with many of my significant creature encounters.

#9

I FREAKING FOUND IT!

It’s in the GM’s Guide section. Master Edition page 83 or 2E Core Book page 76. Under the section “Target Escalation”, the last two paragraphs of the section.

Phew. I know this was a resolved issue, but I feel better knowing there’s a concrete answer for those who want one.

#10

Nice work finding that piece!

#11

Nat 20 on your perception check! Nice!! :smiley: