Playground, can you help me create a monster?

[Xintas]

My players are trying to recruit a faction into a civil war and, long story short, are going to be tasked with completing a test of strength and one of conviction. I have the conviction test down, but the strength one is proving an interesting challenge.

Essentially, a semi-divine child has the power that the child from "The Regulators" book has, which is that they can create anything they can imagine. Her power is slightly different in that the being in question either had to have existed at some point (think of this like a limitless ultimate power true res) or she has to be intimately familiar with it. The power is under control now, but it was not for a long time. This led to her "creating" the horrible monster from her dreams, which the PC's must kill before the faction will join them.

Here is where it gets a little more fun. The PC's are a fairly large group of completely unoptimized characters (Factotum, Warlock, Sorceror, Samurai/Kensai, Monk, Homebrew Duelist/Face type character, and one new person joining in) at level 7. Obviously this creature is going to have a ton of health to force them to beat up on it for a while and all get involved, but what Ex/Su/etc. abilities or features would you give this creature to make it a memorable encounter?

[Red Fel]

Pseudonatural creature? Pseudonatural creature (http://www.d20srd.org/srd/epic/monsters/pseudonaturalCreature.htm). This is a creature of nightmares; take something already terrifying and stack the "look it's a Lovecraftian horror" template on it.

Note that this is an epic template, so for obvious reasons it might take some toning down for a non-epic party to be able to survive. (Unless you plan for it to be an unkillable encounter that they have to resolve in other ways.) There are non-epic versions in a few books, as I recall.

Additionally, pretty much any Far Realms creature qualifies as nightmarishly horrific, although again you're reaching into epic levels.

For kicks, you could always give it the Live My Nightmare (http://www.d20srd.org/srd/variant/buildingCharacters/spelltouchedFeats.htm#liveMyNightmare) spelltouched feat. When you look into the abyss, the abyss freaking up and kills you.

[Azoth]

I kind of like the idea of a Mineral Warrior Greenbound Phase Spider. It is CR8, comes with 2 different kinds of DR, Fast Healing built in, and has several SLAs Entangle and Wall of Thorns most notable. 1/day can deliver a really nasty hit to a player thanks to Mineral Warrior.

The imagery is also cool.

Before you stands a spider twice as tall as the talest amongst you. You can hear faint grinding and rustling as it shifts almost imperceptibly. The small stones near its joints crack against one another to reveal patches of silverish white flesh beneath for but a moment before the hairlike vines that cover its body shift over to hide the few vulnerable spots from you. Long fangs that glint like diamonds run with faint lines like they were veined by the lightest of emeralds before you realize that is its deadly venom flowing forth as it anticipates a meal. Each of you clearly see your reflection cast in eyes like perfect onyx orbs the size of your fist.

Just as you begin to ponder this strange creature it lets loose a horrid hiss like an ax taken to the grind. Its vines flailing before it as the air ripples silver for a flash, and then you see nothing. The only trace it was ever there are the deep indentions its feet left in the soft ground and the scattered leaves falling to the ground when there is no tree in sight.

*The next round it rematerializes and bites someone before going etheral again. All they get to hear are the screams of a party member being bitten*

[Fax Celestis]

Terrifying abominations I've made that you could use:

Ghulurak (http://www.giantitp.com/forums/showthread.php?t=56409), Half-Farspawn Spellwarped Voidmind Dark Advanced Frost Worm (CR 18)
Dappidoc (http://www.giantitp.com/forums/showpost.php?p=3227211&postcount=186), the Divine Pseudonatural Paragon Damn Crab (CR 33)
Helcaerfax (http://www.giantitp.com/forums/showthread.php?t=63584), Apocalyptic Voidspawn Advanced Huge Monstrous Crab (CR 22)
Steena Delphinnia, (http://www.giantitp.com/forums/showthread.php?t=63989) Immortal Blind Oracle Half-Beholder Medusa Monk 3 (CR 12)
Uthilamus (http://www.giantitp.com/forums/showpost.php?p=9254742&postcount=1), Half-Illithid Voidmind Dire Weasel (CR 5)
Skyfire Rake (http://www.giantitp.com/forums/showpost.php?p=9257105&postcount=9), Fire Element Half-Fire-Elemental Dreadnaught Quickened Roc (CR 14)
Blightwolf (http://www.giantitp.com/forums/showpost.php?p=9257828&postcount=12), Evolved Gravetouched Ghoul Half-Fey Half-Troll Phantom Blink Dog (CR 8)
Warforged Battlemanufactury (http://www.giantitp.com/forums/showpost.php?p=9272676&postcount=18), Spellwarped Siphon Legion Warforged Titan (CR 22)

[Xintas]

Thanks for the quick suggestions! I really appreciate it and I think the feel is in line with what I am looking for.

Unfortunately, I have one player who likes reading Monster Manuals, so I want this to be an original monster. Are there any abilities or features in particular you would recommend to give that flavor of "unimaginable terror, but clearly dreamed up by a child"?

[docnessuno]

If you are asking us to build a homebrew monster for you, well that can be done, but YOU should provide the flavor and general abilities (in descriptive terms, opposted to actual crunch) of the monster you want.

[Dr. Cliché]

TUnfortunately, I have one player who likes reading Monster Manuals, so I want this to be an original monster. Are there any abilities or features in particular you would recommend to give that flavor of "unimaginable terror, but clearly dreamed up by a child"?

Just going to leave this here:

http://s2.wallls.com/images/7/1920x1080/wallls.com-35498.jpg

[Fax Celestis]

Well, there are these:
Cerberus (http://www.giantitp.com/forums/showthread.php?t=193352)
Cataclysm (http://www.giantitp.com/forums/showthread.php?t=173921)

The cataclysm in particular is amazingly customizable. No two cataclysms look the same. Give it a try?

[Xintas]

A more realistic and....cthulu-esque Tibbers would actually be kind of perfect. I wish I could give more information on what I am looking for, but I was trying not to step on ideas.

I am going to give it a ton of hp so that they can beat on it, relatively low ac/ref saves, high fort, unreasonably high will, and I want it to be able to interact/attack 4/5 people a round.