Monstrous Physique — Yrthak (2E)

Hey, there! Last week, Ryan was kind enough to cover this slot with a fearsome froggish foe for fighting friendly players. I know he’s been wanting to bring the froghemoth to 2E for some time, but it’s not the only monster he’s wanted to see. So, to thank him for helping cover me last week, I figured I would snag the other 1E monster that he feels deserves a conversion: the yrthak! Let’s see how things ended up!

I want to talk about the process for the conversion much like Ryan did last time. I think it can be helpful to see the steps of the conversion and understand the reasoning for the choices made.

First off, I needed to find a level 9 creature that worked as a good starting point. Luckily for me, the roc is a level 9 creature that covers so much of what we need. In fact, the roc was such a good starting point that I got to use most of what it had with very little change. I kept the same base stats (AC, saves, attack bonuses, etc.) and worked on providing the abilities that make the yrthak what it is.

More than it’s attacks, I think the yrthak’s blindness helps make it distinct. Very few creatures work with such specific senses as echolocation and the yrthak relies on it almost entirely. It was easy enough to snag the echolocation mechanics from the giant bat and bat swarm, but I needed to explain its blindness as well. The 1E yrthak’s blindness granted it immunity to illusions and gaze attacks and the like. While I could have added an immunity that called out illusions and gaze attacks, 2E’s trait system made it easier to cover those and any other similar effects that I felt would be covered by the blindness. I just stated it was immune to visual effects, that is, all effects with the visual trait. Suddenly, I can be sure that the yrthak is immune to effects that would be logical without having to anticipate or future-proof it in the ability. The trait does all the heavy lifting for me.

The yrtahk does have two unique attacks: its sonic lance and explosion. Sonic lance was originally limited to once per round, but I eased up on the restriction and just made it the standard ranged Strike for the yrthak. I didn’t even need to mess with the damage, because I just converted roc’s wing attack into the sonic lance. By doing it this way, I know that the damage value is in a good spot. The explosion needed a bit more bite, however. It originally dealt 2d6 piercing damage to nearby creatures, but required a standard action. Even if you catch a lot of creatures, it felt kind of weak, especially for a CR 9 creature. Instead, I chose to make it more potent in the damage department, increasing it by quite a bit, but limiting its repeated use, much like a dragon’s breath weapon. I also chose to make it a basic Reflex save to make it as simple as possible. Unfortunately, the roc had no DC as part of its stats, so I had to go find one. Rather than use the standard DCs in the GM chapter, I looked at a different level 9 monster. The nessian warhound proved the perfect candidate, as it had a breath weapon that served much of the same purpose. I snagged the DC and the damage value and I was good to go!

I considered coming up with more abilities for the yrthak to follow in the 2E tradition of interesting and memorable abilities, but I felt that it had enough to work with. It has a unique sense that can be beaten with the right condition and it has a big memorable attack in the form of its Explosion. There’s something to be said about the simplicity at play here. All that was left to do is follow Ryan’s lead an snag the yrthak lore form 1E to explain the yrthak. I think after getting this done, I grew an appreciation for the yrthak and I hope you decide to make use of it in your game.

I’ll be taking a short break for the next two weeks during our Guest-tober block, but I will return with more monsters for you soon! If you have any requests for more 2E conversions or Starfinder monsters, please drop me a line at KnowDirection@hotmail.com.

Yrthak                            Creature 9
N, Huge, Beast
Perception +18; echolocation (precise) 120 feet
Skills Acrobatics +15, Athletics +21
Str +8, Dex +2, Con +5, Int –4, Wis +1, Cha +0


AC 27; Fort +20, Ref +17, Will +16
HP 180; Immunities sonic
Blind A yrthak is almost entirely blind and relies exclusively on its echolocation to discern its surroundings. It is considered blind to anything beyond the range of its echolocation. A deaf yrthak is also effectively blind, except against adjacent creatures. A yrthak has weak eyesight that allows it to sense adjacent creatures, though such creatures are always considered concealed. Due to its blindness, a yrthak is immune to all visual effects.


Speed 20 feet, fly 60 feet
Melee [one-action] beak +21 (reach 10 feet), Damage 2d10+12 piercing
Melee [one-action] talon +21 (agile, reach 10 feet), Damage 2d8+12 slashing
Ranged [one-action] sonic lance +21 (range increment 60 feet), Damage 2d6+10 sonic
Explosion [two-actions] The yrthak fires a sonic lance at the ground, a large rock, a stone wall, or a similar nonmagical object that can shatter into smaller pieces within 60 feet. The object shatters into shrapnel that deals 10d6 piercing damage (DC 28 basic Reflex save) to all creatures within 10 feet of the object. The yrthak can’t use Explosion again for 1d4 rounds.

Swift, cunning, and perpetually ravenous, the yrthak terrorizes the barren wastelands in which it makes its home, swooping down from on high to blast prey with bursts of pure sound. Though technically blind, as its eyes are tiny and barely capable of vision beyond a few feet, the yrthak senses its surroundings via acute hearing and echolocation. While its powerful jaws and claws are equally capable of taking down opponents, the yrthak generally prefers to wheel through the sky on its membranous wings, firing bolt after bolt of sound into its prey, and exulting in the thrill of the hunt. An adult yrthak is 20 feet long and weighs 1,500 pounds. Yrthaks spend most of their time aloft—a yrthak hunt often lasts several days, with the yrthak skimming roughly 100 feet over the ground in its wide-ranging search for live prey, only resorting to grazing on carrion in direst need. While they have near-human intelligence, yrthaks generally do not seem interested in forming societies of their own—although the sight of a clutch of yrthaks tormenting a captured morsel might seem to indicate otherwise.

Luis Loza

Luis Loza is a developer at Paizo, working on the Pathfinder World Guide line and formerly on Campaign Setting and Player Companion lines. He's done freelance for Paizo Inc, Legendary Games, Rogue Genius Games, and more third-party publishers. His hobbies include gaming both tabletop and video, making jokes, obsessing over time travel, taking naps with Nova the cat, and walks with heather the wife. He is eternally plagued with a hunger for tacos.

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