Building a Better Improved Uncanny Dodge

[maggot]

I never liked Improved Uncanny Dodge (cannot be flanked) because of that weird clause about "a rogue of 4 levels higher can still flank you."

First it seems to binary: if that rogue is one level higher you would take an extra 8d6+1/hit, but alas you take just 1d6+1 from his shortsword. Works the other way around too where you need to be just one level higher to do decent damage.

Second, with multiclassing, and all the classes that have sneak attack and sneak-attack-like abilities, and at different rates, how do you determine when someone is 4-levels higher in the appropriate classes.

Lastly, it is pretty dang ineligant.

So I'm looking for something better. Any ideas?

One idea would be to reduce sneak-attack/surpise-attack damage by a number of dice. So a barbarian 5 could reduce SA by 2 dice + 1 die/2 levels or some such.

 

[ValhallaGH]

You can be flanked by someone with dice of Sneak Attack greater than one half your Base Attack Bonus plus two.

If:
# SA dice > (BAB/2)+2
Then:
Can be Flanked.

So a Barbarian 15 has a BAB of 15. 15/2+2 = 9. A foe needs more than 9 dice of sneak attack (10 or more dice) to flank a Barbarian. Minimum Rogue level is 19.

A Barbarian 10/Rogue 5 has a BAB of 13. 13/2+2=8. A foe needs more than 8 dice of sneak attack (9 or more dice) to flank this barbarian. Minimum Rogue level is 17.