What 24th level monsters need converting?

[the Jester]

Hey all, I'm working on a project to convert a ton of monsters from earlier editions that I think are cool and deserve it. I would appreciate any input you might have on what monsters would be cool to convert that would have a lower level of 24.

Here's what I have on the list so far, as well as the source I'm using as my primary inspiration:

24th Level Monsters on the List
Crawling Head [24th level] (3e Fiend Folio)
Megalodon [24th level] (various)
Plasm [24th level] (Spelljammer iirc?)
Ruin Chanter [24th level] (3.5 MM5)
Scyllan [24th level] (Stormwrack)
Ungulosin [24th level]

24th Level Variants I've Already Done
Cunning elder behir (level 24 artillery)
Dragon turtle (level 24 artillery) Turtle
Abyssal morkoth (level 24 solo controller)
Living wall shrouder (level 24 controller)
Energized copper horror swarm (level 24 minion skirmisher)
Cloud titan (level 24 elite soldier) giant
Spell eater weaponcharged (level 24 soldier)
Sperm whale ascetic (level 24 soldier)

Higher Level Monsters to be Converted
Beholderkin, Hive Mother [29th level]
Blackball [30th level]
Corpse Gatherer [25th level]
Corrupture [30th level]
Deepspawn [27th level]
Elder Brain [30th level]
Elemental, Omnimental [26th level]
Elemental, Tempest [25th level]
Fiendwurm [27th level]
Flesh Jelly [26th level]
Froghemoth [25th level]
Gargantuan, Devastation Spider [27th level]
Genius Loci [30th level]
Golem, Adamantine [30th level]
Golem, Mithril [26th level]
Hellwasp Swarm [26th level]
Infernal [30th level]
Juggernaut [28th level]
Ki-Rin [26th level]
Kraken [30th level]
Living Holocaust [27th level]
Marid [25th level]
Nuckalavee [27th level]
Plague Spewer [25th level]
Planetar [28th level]
Plasm, Giant [26th level]
Siege Beetle [27th level]
Sirrush [25th level]
Solar [30th level]
Uvudauum [25th level]
Zaratan [27th level]