(READ ME) Mobs that are displaying blank entrance messages.

[DeathCow]

I'd chk if i wasn't at work, its possible that there are line breaks at the begining of those movement/entrance messages.

[The Crazy Animal]

is very possible...

[ms233]

you can add giant crocodile (misty swamp) to the list

edit:  and bandit leader, same neighborhood
and brigand (dragonteeth hills)
tortured spirit, white marble corridor

[strantheman]

Not sure what monsters, but some in the NPP (zombies maybe)