Improved Uncanny Dodge (Ex)

At 7th level, a stalwart defender can no longer be flanked. This defense denies rogues the ability to use flank attacks to sneak attack the stalwart defender. The exception to this defense is that a rogue at least four levels higher than the stalwart defender can flank him (and thus sneak attack him).

If the character gains uncanny dodge from a second class (see above), he automatically gains improved uncanny dodge, and the levels from those classes stack to determine the minimum rogue level required to flank the character.