Advancing Monsters

[The_Dood]

I am having difficulty advancing a shadow to the level where it can acquire a new feat. I am unsure about a lot of things (What the new CR is and does the BAB change or not) and would appreciate it if someone could take me through it step by step.

Thanks in advance.

 

[Crothian]

Okay, a Shadow is 3HD and can be advanced to 9 HD as according to the MM.

Then we look at pg 13 of the MM under Undead. We see that a Undead gain a new feat for every 4 extra HD they have. So, the Shadow needs to be 7 HD to gain a feat.

By gaining 4 HD the shadow will gain +2BAB, +4d12 HP, +8 skill points, +1 Fort and reflex save, +2 Will save. And of course the feat. That info is from using the chart on page 13.

CR will be +2, as by the rules in the DMG