Improved Flanking

[Curmudgeon]

The Superior Flanking feat (Dragon # 343, page 93) offers an increased flanking bonus of +6 to attack. It requires Improved Flanking (+4 to attack) as a class ability, though, which limits its accessibility quite a bit. So far I haven't found very many instances of this class feature.

Swashbuckler level 8 (Complete Warrior, page 12)
Rilkan Rogue substitution level 1 (Magic of Incarnum, page 47)
Wolf Totem option of the Barbarian Spiritual Totem ACF (Complete Champion, page 46) grants a functionally identical ability, but without the name
Am I missing any others?

[whibla]

If all you are after are functionally equivalent abilities then there are / were a couple of feats (3.0) that did this, called Concerted Attack and Team Flanking.

I have a sneaking suspicion that I have seen another class that gives the ability too, but ... where...

[Downysole]

I am not aware of any other sources for improved flanking, but if you are concerned with flanking better, you should consider getting your tank the amulet of teamwork (MIC).

When the wearer and his allies are flanking, they all get +2 untyped damage to their attacks on that creature.

[evil-frosty]

The feat Vexing Flanker(PHB 2) improves the bonus to plus 4 so it is identical to the class feature.

[Curmudgeon]

If all you are after are functionally equivalent abilities then there are / were a couple of feats (3.0) that did this, called Concerted Attack and Team Flanking.
No, I'm really interested in qualifying for Superior Flanking. I have a (small) hope that the DM might allow an identical but unnamed class ability to substitute for Improved Flanking. :smallfrown: