re: Narn Bat Squad

the episode you are looking for is "The Rocks Cried Out, No Hiding
Place" (season 4?), a 
Biblical reference to the book of Revelation where the evil-doers cannot
escape God's justice 
no matter how hard they try.  this alludes to the B5 reference where
Lord Refa (a Centauri) 
cannot escape the justice of the atrocities he commited against the Narn
race.  

the Narn demonstrated their "affection" for Lord Refa's work with
several bat-like objects....

dave