Abyssal Blood Rager and Monstrous Form 2

[ttlovepie]

Abyssal Blood Ragers get
Demonic Bulk (Su): At 4th level, when entering a bloodrage, you can choose to grow one size category larger than your base size (as enlarge person) even if you aren’t humanoid.

And can cast Monstrous form 2. I had a lot of trouble deciphering the polymorph rules, and the fact you can use it even when you aren't humanoid seemed weird.

Do polymorph spells count against "Multiple magical effects that increase size do not stack.?"

[SuperUberGeek]

Yes they do.

[blahpers]

They're pretty much the textbook example of a magical effect that increases size.

Additionally, there's a specific clause vis-à-vis polymorph spells:

Core Rulebook -> Magic -> Transmutation -> Polymorph wrote:

In addition, other spells that change your size have no effect on you while you are under the effects of a polymorph spell.