Wednesday, December 17, 2025

Creature Preview: Bulette

The bulette is a delightful monster whose name I definitely pronounce as “bull-EHT,” not “boo-LAY” as some do. (I have been known to joke that the creature is only pronounced “boolay” if it comes from the Boolay region of Greyhawk. Otherwise, it’s just sparkling landshark.)

The bulette for CORE20 maintains much of the feel of the D&D original. As a tier 3 creature, it makes an excellent solo threat against a tier 1 or tier 2 party, built for power and jumping, and with a prodigious ability to flatten foes. In a recent encounter, I was able to happily confirm that this design had its intended effect when, after watching a bulette break the ground with a surging leap, then drop onto a pack of miniature mammoths they were hunting, the player characters elected to all flee the scene at high speed.

(Click on the stat block header below to download the full stat block in PDF.)




Friday, December 5, 2025

Creature Preview: Cheetah and Hippopotamus

A half-dozen or so new creatures will be making their way into the already-well-populated “Animals” section of the CORE20 Creature Playtest Package, including the cheetah and the hippopotamus.

The cheetah was a creature I’ve wanted to set up for CORE20 for a while now, just because translating the speed of their 70-mile-per-hour sprint into game terms gets really weird. I also liked the idea that cheetahs in our world are known for almost never attacking humans, which makes them a bit novel for carnivores.

The hippopotamus was another animal I wanted to have a CORE20 version of, because it’s well known that the hippo is one of the most dangerous large animals in our world in terms of the number of people they kill annually. And because that’s a well-known fact, many players are aware of it, which means it’s great fun to see their reactions when an adventuring party runs into a hippo in a fantasy world.

(Click on the stat block headers below to download the full stat blocks in PDF.)




Tuesday, November 25, 2025

Creature Preview: Warrener and Xorn

Two of the coolest monsters adventurers are likely to meet underground are the warrener — built from D&D’s umber hulk — and the xorn. Both are weird looking, not necessarily a threat unless you end up annoying them (intentionally or otherwise), and far more sapient than their appearance suggests.

The umber hulk was considered product identity in the original days of the Open Game license (as with the displacer beast). But with the movement of the Dungeons & Dragons SRD into Creative Commons, there are no prohibitions on a game built around the chassis of D&D (as CORE20 proudly is) from getting their umber hulk on. That said, that name always seemed a little meh to me, so “warrener” takes its place — from the way the relentless digging of these creatures creates warrens that wary underground adventurers learn to watch for and avoid.

One big update made to the warrener involves replacing the umber hulk’s confusion gaze with a slowing gaze. It was CORE20 developer Aaron Gray who pointed out to me that confusion effect of the umber hulk feels strange as an evolutionary defensive or offensive strategy, given that a creature under its effect is just as likely to attack the umber hulk as to flee them or stand fast. By slowing other creatures, the warrener is in a better position to catch up to prey, or to evade threats or creatures they just want to ignore.

(Click on the stat block header below to download the full stat blocks in PDF.)

Stat block headers for the warrener and the xorn.



Tuesday, November 18, 2025

Creature Preview: Cyclops

When D&D was in its earliest days, giants were the well-known core of the so-called “true giants” — hill giants, fire giants, frost giants, stone giants, cloud giants, and storm giants — alongside lesser “giant-like” creatures such as ettins and ogres. As the game expanded, it made “giant” into a formal creature type and added other folk to that type. But in so doing, it created a kind of schism in the giants, whereby folk such as cyclopses and fomorians couldn’t be a part of the core identity because they were effectively an afterthought to it.

For both the fomorians (still awaiting final development) and the cyclops, I wanted to work with the idea that they were effectively peers of the core six giant peoples (renamed in CORE20 as the hallaek, the wiirdhar, the fiirmar, the rohkhad, the clohmad, and the istruhmad, because having sapient creatures with advanced and ancient cultures named in the languages of other cultures is part of that colonialism thing that D&D has long struggled with). But even as peers, cyclopses and fomorians (as athachs, ettins, and ogres) needed to be set up as outcasts from the core giant culture in some way. 

The specific angle for the cyclops and fomorians that appealed to me is that they have a connection to druidas magic, which traditionally isn’t part of the whole giant magical oeuvre. As such, the idea is that the giants have an overall ancient arcane tradition, but those two subgroups started messing around with nature magic and ended up splitting off from the giants’ central culture as a result.

(Click on the stat block header below to download the full stat block in PDF.)

Cyclops stat block header.



Monday, November 3, 2025

Creature Preview: Praetyrian and Venenatus

Two new drakes — lesser dragons related to the true dragons — are set to appear in the upcoming CORE20 Playtest Creature Package update. The praetyrian is built around the guard drake of D&D 5e, but felt like they needed a less mundane name. The venenatus is a brand-new creature created for CORE20 — a drake who feeds on magic, often of the sort carried by characters. 

When I wrote the first version of the venenatus (colloquially known as the dweomer drake) for a campaign, it was an original-to-me concept. The Forgotten Realms dweomervore (a similar theme, but very different execution) came to my attention only afterward, with the venenatus mostly inspired by the magic-eating disenchanter (another creature I use a lot, much to my players’ dismay).

(Click on the stat block header below to download the full stat blocks in PDF.)

Stat block headers for the praetyrian and the venenatus.


Friday, September 26, 2025

Creature Preview: Wurfrur and Vocoeur

The blink dog and the displacer beast are two of the creatures I most remember falling in love with when I started playing D&D. Good-aligned extradimensional dogs ? Predatory phasing cats? An ancient enmity between them? Sign me up!

An interesting thing about blink dogs is that they’re sapient, meaning they’re not only intelligent but they have their own language. In AD&D, displacer beasts didn’t speak, but they gained that ability and an evil alignment in the 3e days, both of which they retain in CORE20. When I shared the ohoomwi, I mentioned that CORE20 is making a point of having all sapient creatures named according to what they call themselves, so that CORE20 names the blink dog as the wurfrur and the displacer beast as the vocoeur. But the naming of the vocoeur actually has an interesting side story to it.

Back in the early 2000s when Wizards of the Coast opened up D&D to third-party development by way of the Open Gaming License, that license called out elements of so-called “Product Identity” that were declared absolutely off-limits for third-party products. If you wanted to make material compatible with D&D using the Open Gaming License, you couldn’t use the name of the game or the titles of the core rulebooks, or the names of a bunch of planes, or a dozen specific monsters — including the displacer beast. 

Thankfully, with CORE20 built around the Creative Commons version of the Dungeons & Dragons SRD rather than the OGL version, the limitation on using the displacer beast no longer holds.  But what I and a lot of other people found hilarious about the displacer beast being in WotC’s list of “we own this and are protecting it so you can’t use it” monsters in the first place is that the displacer beast was stolen by Gary Gygax when he created it for the AD&D Monster Manual. As Gygax himself talked about openly, the creature’s appearance and abilities were lifted from a short story by science fiction author A.E. van Vogt, in which the creature’s name was Coeurl — with both those names giving the vocoeur their CORE20 identity.

(Click on the stat block header below to download the full stat block in PDF.)

The headers for the wurfrur and vocoeur stat blocks.


Thursday, September 18, 2025

Creature Preview: Peryton

You know you’ve done a good job at bringing a horrifying monster to life when your developer tells you, “Please don’t ever use this in a game I’m playing in.”

A feral magical predator, the peryton is known for their predilection for feeding on hearts — and for the fear that instills in characters who fight them, even before the fight begins. They are a creature both old (in game terms) and new (in real-world terms), having been around since the AD&D Monster Manual. But they were sourced not from ancient mythology (as many of the creatures of early D&D were) but from Jorge Luis Borges’ Book of Imaginary Beings, written in 1957. 

The peryton’s hunger for hearts has traditionally been mostly flavor, with versions of the creature from AD&D through 5e detailing how a peryton will bite out the heart of a hero only once that hero is dead. But for CORE20, I thought it would fun (for the GM; players’ opinions may vary) to tie the peryton’s heart harvesting to the mechanics for death and dying — allowing the peryton to take a fallen character from dying to dead with unforgiving speed.

(Click on the stat block header below to download the full stat block in PDF.)

Stat block header for the peryton.


Torment Temple

Torment Temple  is a new adventure for the CORE20 public playtest, designed for tier 1 characters (including starting characters)! An ancien...