D&D General Obscure one hit wonder monsters

[Voadam]

I also liked the mohrg. Admittedly, it didn't have a great career, but it did get developed into a class in Libris Mortis: The Book of Undead as well as getting a few templated versions in an Elite Opponents web article.

Pathfinder had them as a core bestiary monster as well and fleshed them out a bunch more in Undead Revisited.

 

[Voadam]

I used the Dark Creature template from Tome of Magic on an advanced roper to make it more of an ambush predator in a high level 3.5 game. I remember it being a fairly straightforward template to apply quickly compared to a lot of mechanically fiddly ones with a lot of number recalculation that were fairly typical in 3.5.

 

[Echohawk]

xvarts

I joke. Actually, I'd have to say the Blindheim (flashlight frogs, as we called them)

Both the xvart and the blindheim have appeared in every edition except (as far as I can tell) 4th Edition. The 5th Edition blindheim is in Mordenkainen's Fiendish Folio, Volume 1 which, to be fair, might not be considered to be particularly official, even though it was published by WotC.

 

[Voadam]

I used the Palrethe demon and the Teratomorph from the 3.0 Monster Manual II.

The Palrethe have a neat backstory of being Balors who failed in bids to advance in power and became broken shells of their former selves at a much lower CR and with some powers linked to their broken forms.

The Teratomorph is an extraplanar giant Chaos ooze that has a randomly transforming touch attack. Very flavorful for a sparkly Yog Sothoth type planar chaos encounter.

 

[Stormonu]

Morgh is probably the top.

Also, I used to really enjoy the Eye of Fear and Flame from the Fiend Folio. I don’t recall having seen it appear in any later monster collections.

 

[Alzrius]

I still think the garmorm, which from what I can tell only ever appeared in AD&D 2nd Edition's Planescape Monstrous Compendium Appendix III, was a cool monster. It was basically a human-sized worm that ate people and added their consciousness to its psychic collective, with mouths all over its body, around which faces could be seen pressing out from within its skin.

What stuck with me most about the garmorm was that it perpetually sang out of its many mouths, even when in combat. The book had the following example (and the [snap] entries are it snapping its teeth):

We are many [snap]
We are one
Now we live [snap]
Never done.

Sing of days [snap]
Sing of night
Long to sing [snap]
Show our might.

Join us in eternal song [snap]
Live with us forever strong [snap]
Our choir seeks more of your kind [snap]
Our power grows with each new mind [snap]

 

[Voadam]

Also, I used to really enjoy the Eye of Fear and Flame from the Fiend Folio. I don’t recall having seen it appear in any later monster collections.

4e Dragon Magazine Annual and Dragon 364 (the first one for 4e) had the Flameharrow, "A rare form of undead often mistaken for a lich or skeleton, the flameharrow (sometimes referred to as an “eye of fear and flame”)"

 

[el-remmen]

What about Volts from the 1E Fiend Folio? One of my faves I have used in every edition (maybe there was a 2E MC version)

 

[Voadam]

What about Volts from the 1E Fiend Folio? One of my faves I have used in every edition (maybe there was a 2E MC version)

Yep. In the 2e Fiend Folio.

 

[aco175]

4e Dragon Magazine Annual and Dragon 364 (the first one for 4e) had the Flameharrow, "A rare form of undead often mistaken for a lich or skeleton, the flameharrow (sometimes referred to as an “eye of fear and flame”)"

One of our old DMs used to throw these at us all the time, fearsome monster in the old edition.

I was going to say the deepspawn. I found it handy to use to populate dungeons, but lazy to use at the same time.

I also have a bunch of pictures from DMsGuild that they allow you to use, but find a whole lot of them are something I never seen or would use.