Truly Horrid Umber Hulk CR Horrible?

[Garnfellow]

An umber hulk is a CR 7 Large aberration with 8 HD.

The 3.5 MM has an advanced elite version dubbed the "truly horrid umber hulk," a CR 14 Huge aberration with 20 HD.

But how did they get CR 14? I get 7 + 1 (elite array) + 1 (size increase) + 3 (12 extra HD divided by 4 for an aberration) = CR 12. What am I missing?

 

[Shade]

I agree with your assessment. Methinks the CR is in error.

 

[Qwillion]

I wonder how it would rate using wil upchurch's model from the monster handbook or upper krusts cr rules (grim)