What 13th-level Monsters Need Converting?

[the Jester]

Remind me again what monster books you have, Jester? I keep forgetting.

I personally would like to see the Chaos Beast, but it being a CR7, I doubt you want to bump it up to 13th level.

Most of them.

From 1e, I have the MM, MM2 and FF; all the other hardbacks with the exception of the Cthulhu/Elric version of the DDG; and a crapload of modules and old Dragons, though many of those are in storage.

From 2e, I have most of the MC sets; the Monstrous Manual; one of the Planescape and 2 or 3 of the annual appendices; and a few modules and Dragons here and there, but not many at all. Oh, plus the Planescape basic set.

From 3e, I have the MM1-5, FF, the environment books, Tome of Horrors, Monsternomicon, most other WotC non-setting-specific hardbacks (many of which have a monster or two in 'em)

I'm also happy to steal from other games that I have, but there aren't too many of those with suitable things anymore. (I do have several monsters that you'll see loosely converted from Arduin, though.)

Edit: Oh, and chaos beast- good call!

Hmm, I might as well throw it in and turn it up to mid-paragon. It's a planar threat, right? We'll set it at level 15...

 

[Rechan]

Here's a thought:
Entombed (Frostfell). CR 10, but would make a fine 13-14th level foe, on par with the Archons.
Chillbain (Frostfell) CR 18.
Deathjack (Monsternomicon) CR 15

 

[the Jester]

Ooh, more great ones! Added them all for higher levels, along with a few others that I thought of that I really want to make sure I get... you'll notice that a bunch of them are originally from Return to the Tomb of Horrors, possibly the single best 2e product imho.

 

[Rechan]

Here's another one:

Tempest (MM II) CR 16. Although it might be on par with Storm Titans or storm giants, or maybe they're the messangers of Storm Titans (Therefore, a level or two lower).

One thing I'd like you to do, Jester, are a few templates. Like Monster of Legend, and a few others. Just as a break from the ye olde monster conversions.