The most unbalanced monsters for each CR up to 20 (or so)?

[Incanur]

Consider steel dragon great wyrm for CR 18. Casts as a 21-level sorc, 536hp, 44 base AC, etc.

[Isamu Dyson]

Consider steel dragon great wyrm for CR 18. Casts as a 21-level sorc, 536hp, 44 base AC, etc.

Which book do they debut in?

[Vedhin]

Which book do they debut in?

Online, IIRC. I'll be back with a link if so.

Link

[Incanur]

I'm familiar with steel dragons from Dragons of Faerun. But they are online: http://www.wizards.com/default.asp?x=dnd/mm/20040328a. They're potential contenders at almost any CR because of the sorc casting. A young dragon has 85hp and caster level 5 at CR 4, etc.

[Silva Stormrage]

Beholders are pretty dang lethal and might qualify for the cr 13 spot.

Elemental Weirds also should get in this CR 15 casts as an 18th level sorcerer with bonuses and massive divination bonuses.

Also there might need to be a spot for templates too. Vampire is pretty dang strong for +2 CR.

Edit: Spectral Lyrists from Libris Mortis are also deadly for the same reason as Allips. CR 4, 33% more hit points than an Allip, extra damage (And to a common dump stat) but the damage allows a save (Which is high at 18 and increases each time the creature uses the touch as the touch grants 1 charisma to the spectral lyrist. That paired with the fact that it can disguise itself incredibly well and also use suggestion on creatures. It can be a PAIN to fight at that level.

[Vedhin]

Elemental Weirds also should get in this CR 15 casts as an 18th level sorcerer with bonuses and massive divination bonuses FREE ACTION DIVINATIONS.

Fixed that. If the DM does not enforce a limit on free actions/round, a intelligently played Elemental Weird wins. That's against anything not named Pun-Pun. They still have a fighting chance against Pun-Pun, as they can ensure he never ascends.

For CR 6, the Gravbeast is a contender. Powerful Pounce is the big thing, giving it 6 attacks dealing 2d6+4 damage. Reverse Gravity and Gravitic Turbulence are a nasty combination.

[Silva Stormrage]

Fixed that. If the DM does not enforce a limit on free actions/round, a intelligently played Elemental Weird wins. That's against anything not named Pun-Pun. They still have a fighting chance against Pun-Pun, as they can ensure he never ascends.

For CR 6, the Gravbeast is a contender. Powerful Pounce is the big thing, giving it 6 attacks dealing 2d6+4 damage. Reverse Gravity and Gravitic Turbulence are a nasty combination.

Fair enough Though its not necessarily an instant win, an epic level wizard with mind blank up 24/7 can still win

[Karnith]

Also there might need to be a spot for templates too. Vampire is pretty dang strong for +2 CR.

Half-Celestial and Half-Fiendish can also be pretty silly, since they grant SLAs based on HD.
If you're wondering why I bring this up a lot, it happened to me.
Why, hello there CR 12 Half-Fiendish Air Elemental, with your fly speed of 100 ft. (perfect) and CL 21 Blasphemy.

[Isamu Dyson]

Some Epic Level monsters (from the Epic Level Handbook) are terrible for their assigned CRs.

Here is one example. Wouldn't a CR 23 dragon likely be a bigger threat?

[Karnith]

Here is one example. Wouldn't a CR 23 dragon likely be a bigger threat?

Given that a Brachyurus can't really do anything to flying enemies, yes.

WotC didn't really know what they were doing when they CR'd a lot of 3.0 creatures, and epic levels are pretty broken anyway. I suspect that darts and boards were involved.

[Isamu Dyson]

Given that a Brachyurus can't really do anything to flying enemies, yes.

WotC didn't really know what they were doing when they CR'd a lot of 3.0 creatures. I suspect that darts and boards were involved.

At which CR/ECL is flight capability a necessity for a monster to be a threat?

[Big Fau]

At which CR/ECL is flight capability a necessity for a monster to be a threat?

PCs get flight at level 5, maybe 6.

[Vhaidara]

Edit: Spectral Lyrists from Libris Mortis are also deadly for the same reason as Allips. CR 4, 33% more hit points than an Allip, extra damage (And to a common dump stat) but the damage allows a save (Which is high at 18 and increases each time the creature uses the touch as the touch grants 1 charisma to the spectral lyrist. That paired with the fact that it can disguise itself incredibly well and also use suggestion on creatures. It can be a PAIN to fight at that level.

Seconded, as someone who has had to fight one. 6 level 5 PCs, including a Sun/Healing/Radiant Servant cleric, and only 1 person made their save. Almost wiped us.

[Vedhin]

Fair enough Though its not necessarily an instant win, an epic level wizard with mind blank up 24/7 can still win

No. He can't. The Elemental Weird's Prescience ability is as follows:

Prescience (Su): At will and as
a free action, a weird can duplicate the
effect of any of the following divination
spells: analyze dweomer, clairaudience/clairvoyance, contact other
plane, detect thoughts, discern location, find the path, foresight,
greater scrying, legend lore, locate creature, locate object, tongues,
true seeing, vision. Caster level 18th; save DC 16 + spell level

The key is Contact Other Plane. Essentially, the Elemental Weird plays 20 Questions with Cthultu. Or some other entity, but Cthultu is funnier. And it gets as many questions as it wants. It can locate things indirectly, by asking questions like "If I were to teleport a grain of sand to coordinates XYZ, would the spell fail?" It asks this question a bunch of times to even out the probability, and selects the true answer from there. The indirect questioning doesn't actually reveal information about or target the wizard, so Mind Blank does nothing.

[Silva Stormrage]

No. He can't. The Elemental Weird's Prescience ability is as follows:

Prescience (Su): At will and as
a free action, a weird can duplicate the
effect of any of the following divination
spells: analyze dweomer, clairaudience/clairvoyance, contact other
plane, detect thoughts, discern location, find the path, foresight,
greater scrying, legend lore, locate creature, locate object, tongues,
true seeing, vision. Caster level 18th; save DC 16 + spell level

The key is Contact Other Plane. Essentially, the Elemental Weird plays 20 Questions with Cthultu. Or some other entity, but Cthultu is funnier. And it gets as many questions as it wants. It can locate things indirectly, by asking questions like "If I were to teleport a grain of sand to coordinates XYZ, would the spell fail?" It asks this question a bunch of times to even out the probability, and selects the true answer from there. The indirect questioning doesn't actually reveal information about or target the wizard, so Mind Blank does nothing.

But it can't spam contact other plane. It doesn't have enough intelligence to make the check reliably enough to actually use it that frequently.

Another monster that is probably undercr'ed

http://www.d20srd.org/srd/monsters/ghaele.htm
CR 13, casts as 14th level clerics with a BUNCH of good SLA's. Not sure if its the strongest but its pretty deadly.

[Vedhin]

But it can't spam contact other plane. It doesn't have enough intelligence to make the check reliably enough to actually use it that frequently.

Prescience is (Su), so no minimum Int/Cha is needed. If it fails a check, it just tries again.

[Eldariel]

I mean, for CR 21 we probably have to go with Sarrukh. Serpent Kingdoms, it has the most unfortunately worded ability ever in "Manipulate Form", which effectively says "do whatever you want to a scaled one of Toril". I mean, yeah, it's CR 21 and Manipulate Form does cause system shock but...small price for literally limitless power.

[Battleship789]

Planetars are pretty nasty for CR 16: Cleric 17 casting, Regeneration, SR 30, and a pretty good SLA list.

[lunar2]

well, for just being straight up under CR'ed, i'd say the greater barghest at CR 5. as printed it's at least a CR 7, and properly advanced (WotC made a bunch of mistakes advancing from the barghest) is closer to CR 8.

[Eldariel]

The worst part about Elemental Weirds is that Prescience is (su), they're 15 HD (within Polymorph/Metamorphosis limits), Elementals (no type shenanigans needed) and Assume Supernatural Ability/Metamorphic Transfer are things. Ergo, if PCs ever hit 15 HD even for just few moments (say, with an Inspire Heroicsing Bard with Words of Creation) or if somebody tosses Polymorph Any Object their way (it apparently doesn't care about HD, being able to turn a Lizard into a Manticore), they can be turned/turn into an Elemental Weird and get that ability and basically gain omniscience in the span of one round.

[Kuulvheysoon]

Although less terrifying than the fossil, it's an official creature: The living burning hands, from the ECS. The scary part being DR 10/magic at CR 1. Other than that, it's got 5hp, pitiful AC and low damage.

Living sleep/color spray are scarier, but that's just judicious use of the living spell template.

[erikun]

This thread might be worth looking into. Just taking a look at the first page, I'm seeing Hammerclaw (Stormwrack), Cloaker Lord (Monsters of Faerun), Adamantine Horror (MMII), and Ephemereal Swarm (MMIII) are worth looking at.

[Phaederkiel]

I personally have a soft spot for Murderjacks at cr 9 ( I almost managed to wipe a lvl 12 Party with one of those guys...), 10th lvl Bard casting, frightening presence, lotsa HP, 7d6 sneak, damn good skills, miss chance, and the worst: clever combat tactics.

http://www.wizards.com/default.asp?x=dnd/fw/20040828a

and I have to wonder why the assasin vine is not mentioned, old killer that it is. I mean, it obviously cannot hold a candle to the incorporeal nasties, but it still pack a punch, and the entangle is quite dangerous. Combined with its stealth abilities, it has great capabilities to kill a character. And it is Core. That should count for something.

[Isamu Dyson]

Planetars are pretty nasty for CR 16: Cleric 17 casting, Regeneration, SR 30, and a pretty good SLA list.

Planetars are rather tough for ECL 16, yeah.

[Phaederkiel]

oh, and the sharn seems to be good for cr 8:

http://www.minmaxboards.com/index.ph...81573#msg81573

[Isamu Dyson]

well, for just being straight up under CR'ed, i'd say the greater barghest at CR 5. as printed it's at least a CR 7, and properly advanced (WotC made a bunch of mistakes advancing from the barghest) is closer to CR 8.

What makes the Greater Barghest noteworthy?

[Zanos]

Planetars are rather tough for ECL 16, yeah.

Considering the fact that a 17th level cleric is CR 17, planetars are just broken. Cleric 17 with regeneration and resistances, outsider hit dice, etc...

Clearly all those special qualities make the cleric casting worse somehow.

[Isamu Dyson]

Considering the fact that a 17th level cleric is CR 17, planetars are just broken. Cleric 17 regeneration with regeneration resistance, outsider hit dice, etc...

Clearly all those special qualities make the cleric casting worse somehow.

Might not some or even all of those "icing on top" abilities be replicated by a Level 17 equipment loadout?

[Rubik]

Anything with the greenbound template, especially for a summoner with the Greenbound Summoner feat.

Cast a 1st level Summon Nature's Ally to gain a creature that can cast two 1st level spells and one 3rd level spell at will, as well as one 5th level spell 1/casting?

Plus, at higher levels especially, it's a plant with an extra +6 natural armor, DR 10 magic and slashing, fast healing 3, +4 to grappling, cold and electricity resistance 10, tremorsense 60', Str +6, Dex +2, Con +4, Cha +4, +16 to Hide and Move Silently while in forested areas, and an extra slam attack.

That's really nice, and it only costs one feat for the summoner.

[TuggyNE]

Might not some or even all of those "icing on top" abilities be replicated by a Level 17 equipment loadout?

Not really, since the Planetar also gets gear, though not as much.