Cloak of the Manta Ray and Enlarge Person

[Chuck Mount]

Wondering if there's a rule clarification about using Enlarge Person while under water with a Cloak of the Manta Ray.

The description of the cloak states that the wearer appears identical to a manta ray as per the Beast Shape II spell. That states that you assume the form of an animal.
The Enlarge Person spell states that the target is one humanoid creature.

So... Obviously if you assume the form of something, your form changes, but are you still a humanoid type or does your type change to animal because you assume the form of a manta?

In our game, we're assuming the type changes to animal, but I was wondering if a rule was actually made on this.

[Name Violation]

Enlarge person doesn't work with polymorph effects, such as beast shape.

They dont stack, but not for the reasons you listed

[Chuck Mount]

What are the other reasons they don't stack?

[Chuck Mount]

Never mind. I asked before I Googled it. Thanks.

[bono_bob]

Why don't they stack?

[vhok]

bono_bob wrote:

Why don't they stack?

the rules say polymoph effects don’t stack

[avr]

Enlarge isn't a polymorph, but 'In addition, other spells that change size have no effect on you while you are under the effects of a polymorph spell.'

[willuwontu]

Not to mention the whole FAQ on Size Increases that says only one size increase applies at a time.