Customizing improved monsters?

[Tanuki Tales]

Is anyone aware if there is a third party book or something similar that went into rules for giving new traits and features to monsters that are advanced by HD?

It's easy to just slap class levels or templates, but it'd be neat if there were options like dragons or some other monsters get for advanced by their RHD.

[rrwoods]

Officially, you give the monsters skill points, feats, and hit points according to their HD. It's no different from building a PC in that regard.

If you're looking for a way to give the monsters what would be the equivalent of more racial abilities, a set of rules for that would be so intricate as to be unreasonably cumbersome. It would be more useful to have a compilation of such abilities put together by the community, but I'm not aware of any such list.

[Blackhawk748]

Generally i just slap the new ability on it and increase its CR by at least 1, sometimes more if the ability synergizes really well.