Barbarian Rage + Racial HD + Alternate Form?

[Tragak]

If - for example - I had a Quasit with 1 level in Barbarian, and he AlternateForms into a Wolf, then 1) would he keep his Rage ability (I don't see why not, but it's been a while for me), and 2) if so, how would the Racial HD impact the HP gain?

Even if a QuasitWolf can Rage, the fact he now has 15+4 CON instead of 10+4 CON does not impact HP, so would the QuasitWolf gain 8 HP (2 from CON * 3+1 from Racial&Class dice) or 2 HP (2 from CON * 1 Class level)?

[Biffoniacus_Furiou]

Alternate Form specifically makes the creature retain its original hp total which is what a Quasit uses, so a Con increase in an alternate form would not change its hp total. It would need to rage before changing forms, in which case the Con increase will affect all of its hit dice, both racial and from class levels. Whirling Frenzy would be better, though.

[Pan151]

Rage interacts with RHD exactly as it does with any Hit Dice.

He would keep his Rage ability in his alternate form, because rage an Ex ability from a class level - barbarian rage is also the given example of this particular rule

+4 con bonus applies to all hit dice, so he gains 8 HP, regardless what form he is in when using rage. However, if he rages while in wolf form, his rage would last for 7 rounds (3 + 4 from 19 con) but raging while in quasit form will last only for 5 rounds (3+2 from 14 con) regardless of whether or not he changes form later.