I am Cthulhu

[ZiggenTheLord]

Does anyone know the best way to become or play as an Eldritch horror or aberration ESC character ?

[Uncle Pine]

I'm not sure what an ESC character is, but half-minotaur + a few illithid heritage feats + expansion net you a giant tentacular thing with horns and a mind so twisted not even a maze spell can confuse you.

Alternatively, Aberration Wild Shape will let you turn into an aberration yourself, as will bein an elan with access to alter self or similar.

There might be some useful PrCs that give you tentacles and such, but right now I can only think of the Fleshwarper.

[DrMotives]

Primeval from Frostburn gets an animal form and gradually loses points permanently from Int & Cha to gain in the other 4 stats. You can pick any dire animal, dinosaur, or other animal with DM approval. If you pick a giant squid or octopus, it'll be like being an eldritch were-tentacle beast. A refluffing with a permissive DM could net you Otyugh Primeval, which could really work on a barbarian base. It's a lousy choice on a non-warrior type character though.

[Coidzor]

If you're open to homebrew, the Ozodrin is pretty eldritch, I'd say.

[Rhaegar14]

If you're open to homebrew, the Ozodrin is pretty eldritch, I'd say.

Here's a link to the homebrew Coidzor is referring to. (http://www.giantitp.com/forums/showthread.php?153536-Tooth-and-Tentacle-base-class-PEACH) It is very appropriate for this kind of thing.

[QuickLyRaiNbow]

Does anyone know the best way to become or play as an Eldritch horror or aberration ESC character ?

Half-farspawn is a template, albeit not a very good one.

And Soul Eater is a class, as is Warshaper. Combined, you can be a ball of tentacles that drains away life force with a touch. That's fairly eldritch horror-y. What you really want, though, is a gaze attack that causes wisdom damage, and I'm not sure if there is one that's particularly easy to get.

[Uncle Pine]

Half-farspawn is a template, albeit not a very good one.

And Soul Eater is a class, as is Warshaper. Combined, you can be a ball of tentacles that drains away life force with a touch. That's fairly eldritch horror-y. What you really want, though, is a gaze attack that causes wisdom damage, and I'm not sure if there is one that's particularly easy to get.

None of these deal Wisdom damage, but the Opalescent Glare spell (SC) can be used to get a permanent gaze attack. Binders can bind Balam or Geryon. A dracolich's paralyzing gate is most likely a gaze attack as well, but way it's worded is terrible.

[Calthropstu]

You could also try playing as a Kraken.

Though that lvl adjustment would be pretty ummm...

high.

[Mehangel]

If you allow Spheres of Power (http://spheresofpower.wikidot.com/), you can utilize the Transformation feet line and grant the following traits to the Anarchic Transformation (http://spheresofpower.wikidot.com/alteration#toc7) form: Abberant Body (http://spheresofpower.wikidot.com/alteration#toc3), Extreme Adaption (http://spheresofpower.wikidot.com/alteration#toc22), Star-Spawn Transformation (http://spheresofpower.wikidot.com/advanced-talents#toc10). Or you can use the Shifter (http://spheresofpower.wikidot.com/shifter) class and take these talents and/or take bestial traits that give similar abilities.

[ZiggenTheLord]

fleshwarper any good for this ?

[ShurikVch]

It will be easy to give advices, if OP specify better what should be the results

Some stuff (mostly from from magazines):
Aberrant Paragon (Dragon #332) - turn you into aberration in 3 easy steps levels
Unholy Abomination (Dragon #313) - one more 3-level PrC (sadly, doesn't progress CL/ML)
Illithidkin (Dragon #296) - this 5-level long PrC is about serving Illithids and becoming more like Illithids
Thrall of Dagon (Dragon #349) - "Song of Dagon" class feature allow to add Wisdom damage to your [sonic] spells; cast some spell with long duration (or even persist it), and drive bystanders mad 24 hours/day
Thayan Slaver (Unapproachable East) - able to inflict Wisdom damage by successful Intimidation checks

[atemu1234]

fleshwarper any good for this ?

Eh, fleshwarper is usually more about taking bits and pieces from the aberration and sticking themselves on you, rather than becoming an aberration, at least until the capstone.