Old monsters we still haven't seen...

[Li Shenron]

The Catoblepas is in MM2.

Ok I even saw that book but eventually forgot...

 

[Mark Plemmons]

Other official classic monsters in Dangerous Denizens that I don't THINK I've seen elsewhere in the WotC books are the:

Forlarr (formerly Forlarren, I think)
Guardian Familiar
Hound of Ill-Omen
Mite
Poltergeist
Sheet Phantom
Swordwraith (actually, this one ended up as the Skarrnid swordwraith since a WotC swordwraith got published just before this book)

Since the Kingdoms of Kalamar campaign setting is official, I have to keep a closer eye on which monsters they've got coming out coinciding with ours. I ended up leaving out the half-ogre since it ended up in Savage Species (I think).

 

[Richards]

The Sheet Phantom was updated to 3.0 in "The Ecology of the Sheet Phantom," Dragon #276.

Johnathan

 

[Gez]

Forlarr (formerly Forlarren, I think)
Hound of Ill-Omen
Mite
Poltergeist

Those four are also in the ToH. There's also the Pestie to go with the Mite.

 

[BOZ]

yeah, i have noticed how the KoK designers have snuck conversions of little-known monsters into their books. i like!