"We're out of monster ideas for the new book, boss."
"Just throw a few darts at the index page, it's what we did with the dracotaur."
The shrieking terror: a gruesome crossbreed of a hydra and a vargouille that has inherited the former's heads and healing factor, and the latter's shrieks and kisses. For some reason, combining an outsider and a magical beast gives an aberration, which proves that two great things do not always go well together. Fifteen aberration RHD are a lot to be stuck with, after all.
For some, wholly incomprehensible reason, this giant evil hydra-offshoot has thirteen strength and is medium size. That's not just 'somewhat suboptimal stats', that's inferior to multiple PC races, and equal to a bunch more. Its other stats range from somewhat presentable (18 dexterity) to absolutely terrible (5 intelligence).
Natural weapons-wise, the terror has five bite attacks that, with some shenanigans and a friendly fighter, can easily be turned into ten. Each deals 1d6 damage, and also delivers a poison to make said damage unhealable.
A 40 ft. fly speed, fast healing 5, Combat Reflexes and Pounce are all solidly in the realm of 'nice, but not great', especially at the level we're talking about.
Shriek is a reasonable AoE paralysis effect that will be enjoying a rather large bonus from the beast's heads, and can be used on allies as long as they get immunized once a day. It's probably the most notable feature here, for all that that's worth.
Kiss, like I said over a year ago, is bad. It's a save-or-die, but it's a save-or-die that only works on paralyzed opponents, which is a lot like having a lamp that only functions in broad daylight.
The shrieking terror, given its poor RHD, lack of limbs, disappointing stats, and generally poor abilities, is simply outclassed by many other options at this level. -0 LA.
Ten-Headed Shrieking Terror
Five more heads, five more RHD. Credit where it's due: the thing is actually Large now, and has an improved strength of 21 and more bite damage. However, twenty aberration RHD is a lot, and however it's improved this still isn't viable. -0 LA.