Minor update, I have tweaked the
Damage Threshold Rules so that the baseline is now Hit Dice x 0.3 rather than Hit Dice x 0.5.
Behind the Curtain, the new Damage Threshold formula is: (Material* AC x 0.0273 rounded down to nearest tenth) x Hit Dice.
*Not Monster AC
So...
An Adamantine Golem (CR 24 with 60 Hit Dice) would now have Damage Threshold 36; whereas Nezha (also CR 24, 60 HD) would have Damage Threshold 18.
The change is a bit more forgiving. Testing of Boons like
Adamantine (Anvil) Form work better with the new scaling. Right off the bat (Tier 2 Divine Boons...with Tier 1 being Epic Boons) you'll be able to take Boons that give: Stone Form, Steel Form, Elastic Form, Sand Form, Plasma Form etc. and these come with multiple features (usually six) and drawbacks (any more than 3 features need to be cancelled by drawbacks that cannot be mitigated).
While on the face of it, Steel Form would seem more powerful than say Stone Form it might have different Vulnerabilities that mean for your Immortal one might be a better fit over an other. For instance if you are a Sky-god you get Lightning Immunity and Acid Vulnerability (among other things), you probably won't want to take Steel Form which has Lightning Vulnerability and that would supercede your Lightning Immunity, etc. So there is a bit of planning to be done when putting your build together - remembering of course Immortals can change all boons each time they gain a new Divine Rank. So you won't get stuck with a bad choice for too long.
The higher the tiers the more ridiculous the Forms: Quark Form, Anti-Matter Form, Neutronium Form...and those are just the mid tier Boons.
The
Universal Boon Properties table mean you will be able to create your own Divine Boons or Form-Boons within a few minutes. Even though I have a good amount of boons I can't cover every possibility in the book - try as I might. This chapter alone is over 80 pages and counting.