Question on the Blind-Fight feat for Drowned Ones in Tammeraut's Fate(Dungeon #106)

[NPC Dave]

Drowned Ones automatically pick up this feat. Am I correct in assuming that Drowned Ones are not vulnerable to any blindness spell effect because as any undead they are immune to anything requiring Fortitude saves?

They presumably have this feat so they can fight in total darkness such as the deep ocean and reduce their miss chances against any types of concealment.

This is for 3.5 but it probably didn't change in Pathfinder.

[Are]

Yes, that's pretty much correct. In addition, Blind-Fight eliminates (most of) the penalties for fighting an invisible attacker.

Note that there could be blindness effects that don't require a save, as well, although I can't think of any at the moment.