Dragonborn Hengeyokai

[daremetoidareyo]

Does the form that you enter the egg as determine what your form will be?

If a sparrow hengeyokai does the dragonborn thing while in sparrow form, can he come out a tiny firebreathing dragonbird?

[Flickerdart]

No - the true form of a hengeiyokai is the human form, and the animal form is an alternate form which is lost during rebirth.

[daremetoidareyo]

I'm not so sure: "Hengeyokai are intelligent, shapechanging animals, able to shift freely between human and animal forms"

[Darrin]

If a sparrow hengeyokai does the dragonborn thing while in sparrow form, can he come out a tiny firebreathing dragonbird?

I would have to say "No". When they become Dragonborn, hengeyokai retain their humanoid type and shapechanger subtype (as per the OA 3.5 Update in Dragon #318), but they lose their racial "Alternate Form" ability. If they entered the egg in an animal or hybrid form, I would assume they revert to their humanoid form, just as if this were a spell effect that came to an end or was dispelled. But I can't say definitively that this would be RAW.

[Flickerdart]

I'm not so sure: "Hengeyokai are intelligent, shapechanging animals, able to shift freely between human and animal forms"

That's fluff. Look at the rules, especially the 3.5 update in Dragon 318. Hengeiyokai are humanoids with the shapechanger subtype and an Alternate Form ability that lets them become animals.