Q: Summon Monster Spells

[Corinth]

What is the relation between the spell level of a Summon Monster spell and the Challenge Rating of a creature that a caster may summon with that spell?

 

[Mr Fidgit]

i don't think there is a direct correlation or formula for it. if you look at just summon monster IX , the CRs range from 5 (nightmare) to 14 (Astral Deva)

 

[Corinth]

If not by CR, then by HD?

 

[(Psi)SeveredHead]

When you summon a creature, you aren't calling it. Some creatures lose cool abilities when you do so - poisonous creatures become more powerful.

For instance, if you summon a fiendish viper, and it poisons someone, and then it's duration runs out, the victim still has to make another Fortitude save to avoid Con damage. Hence it's CR is lower than expected.

Gelugons have the ability to summon another gelugon, which contributes to its high CR. However, a summoned gelugon cannot summon another gelugon, so a summoned gelugon is weaker than it's CR would indicate.

 

[Mr Fidgit]

If not by CR, then by HD?

again, i don't think so. just a quick look: Deva 14 HD, Xill 5 HD.(Psi)SeveredHead's got the right idea about powers/abilities being a factor, but some choices don't add up. (using the above example, nothing about a Xill compares in 'power' to an Astral Deva (both summon monster IX ))

 

[Corinth]

The lack of a clear pattern behind the lists in the PHB annoy me to no end. It's damned hard to determine where to put anything else--such as an anarchic dire weasel--if there is no pattern for me to follow. If there is one, then I'd appreciate it if someone would spell it out for me.

 

[mkletch]

When you summon a creature, you aren't calling it. Some creatures lose cool abilities when you do so - poisonous creatures become more powerful.

For instance, if you summon a fiendish viper, and it poisons someone, and then it's duration runs out, the victim still has to make another Fortitude save to avoid Con damage. Hence it's CR is lower than expected.

Check the FAQ. Any parts of a summoned creature that are separated from it disappear when the creature does. So poison disappears and does not affect the target if the creature disappears first.

-Fletch!

 

[mkletch]

The lack of a clear pattern behind the lists in the PHB annoy me to no end. It's damned hard to determine where to put anything else--such as an anarchic dire weasel--if there is no pattern for me to follow. If there is one, then I'd appreciate it if someone would spell it out for me.

The selections were just a SWAG by the designers. Add the fact that you can never summon anything outside of the MM, and the attraction of future monster releases is dimmed, at least for those who play more than they DM.

-Fletch!

 

[dcollins]

The lack of a clear pattern behind the lists in the PHB annoy me to no end. It's damned hard to determine where to put anything else--such as an anarchic dire weasel--if there is no pattern for me to follow. If there is one, then I'd appreciate it if someone would spell it out for me.

They're not designed for you to add anything to them. By the core rules, those lists are fixed, so it's not surprising that there's no such facility.

 

[warpmind]

It's really weird to not expand the lists of the PHB. I think WOTC staff assigned the summon level of each creature by playtesting and there's no direct relation between the level of the spell and the CR or HD of the creature.

In RR2 there are spells which try to solve this problem. I think they're called "Summon Specific Creature" or something like that and work by summoning the specific creature the spell was designed to summon. For example, Summon Imp lets you summon only Imps. Summon Xill would be a completely different spell though. The level of the spell is just one half the creatures CR.

It's not as effective as the classic Summon Monster spells but makes Conjurers a bit more creative.