GURPS House Rule: 4d6 for Untrained Skill Attempts

In GURPS, when a character tries something they don’t have a skill for, you usually default to a related skill or attribute with a penalty (often -4 for easy, -5 for average, or -6 for Hard and some VH). This works fine, but it can slow things down. You have to figuring out the right skill being used, checking its defaults, and digging through rulebooks for the exact penalty takes time. The Fantasy Trip has an interesting way to handle untrained use: 4d6

So why not use this in GURPS? If a player wants to try something and doesn’t have an applicable skill, the GM picks the most relevant attribute (DX for physical tasks, IQ for mental tasks, occasionally something like Will or HT for specific cases). The player rolls 4d6 and needs to get equal to or under the attribute to succeed. That’s it. No looking up skills or default penalties.

Critical successes are on a roll of 4, which will be much more rare. Critical failures are on a roll of 17+ will be far more common.

This saves a lot of time, no debating which skill default most fits or where to find the list of defaults. You can still use defaulting to other skills, but only if the player or GM knows for sure what those defaults are, otherwise don't waste the time and just roll 4 dice.

Statistically this is more generous for most skills. 4d6 roll is a bit easier than the standard Average default (-5). For example, with DX or IQ 12, you’ve got about a 22% chance of success, compared to ~16% for a -5 default or ~26% for a -4 default. Due to the way the bell curve distribution works, it ends up being more penalizing for higher attributes over a straight penalty, but I also see that as a feature not a bug.

So anyway, it's a neat quick rule that can save a lot of time and not really mess with balance much.

Quick Cyberpunk Red Game

Over the weekend, I ran a quick adventure using the Cyberpunk Red "Easy Mode" free intro rules. I didn't use the adventure included in those rules, though, and came up with my own. Inspired partly by the Cyberpunk 2077 video game's origin stories, I threw this quick game together and thought I'd share.

(Warning! I don't know Cyberpunk Red that well and just sort of made up a lot on the fly. This very likely has several mechanical mistakes for skill checks, so take it with a grain of salt.)

Yrth as Isekai: Banestorm Meets Manga Tropes

Lately I've been watching a lot of anime with my sons, and something occurred to me. There is a genre of anime called "Isekai" where normal folks get transported into a fantasy world. So I wondered how well that idea overlaps with Banestorm's Yrth which is a fantasy parallel world where occasionally people from our world are teleported into it. Here are some thoughts:

Yrth: The Isekai Starter Kit

If you haven’t read GURPS Banestorm, here’s the gist: Yrth is a fantasy world where a magical backfire called the Banestorm transported people from Earth and beyond into a medieval melting pot. You’ve got Crusader-era Christians, Muslim caliphates, elves, dwarves, orcs, and even weirder stuff like Reptile Men and Sea Elves—all stuck together on the continent of Ytarria. The Banestorm’s been dormant for centuries, but what if it flares up again in 2025? That’s our hook—modern-day players get sucked in, bringing their Netflix binges and Wi-Fi dreams to a world of swords and sorcery.

Turning Up the Isekai Dial

Isekai thrives on a few key ingredients, and Yrth’s got the bones to make them sing. Here’s how we tweak it:

1. The OP Protagonist
   Every isekai needs a hero who’s just too good. When the Banestorm grabs your players—say, a group of con-goers or a D&D crew mid-session—it could juice them up with unique powers, special magical weapons, or some other "cheat" that let's the relatively "normal" power level earthlings have an edge (or at least a chance) in this magical world.
2. “Wait, I Know This!”
   Yrth’s Earth-like cultures are gold for isekai’s “genre-savvy hero” trope. Your players might spot parallels—knights and churches in Megalos, bazaars and minarets in al-Haz—and think they’ve got the upper hand. Until, you know, a wizard turns their “feudalism 101” lecture into a polymorph spell. Bonus points if one player’s a total isekai nerd who starts hunting for “quest givers” in every tavern.
3. The Villain
   Isekai loves a big bad, and Megalos is begging to play the part. Picture its empire as the “evil kingdom”—expansionist, magic-hating, and run by jerks in fancy armor. Or go deeper: the Dark Elves who botched the original Banestorm could still be lurking, or a reincarnated “Demon Lord” who’s also from Earth (and has it's own "cheats").
4. Slice-of-Life Shenanigans
   Don’t skimp on the fun stuff. Let the PCs invent pizza in a Cardiel inn, flirt awkwardly with a Sahud princess who thinks “Netflix and chill” is a battle cry, or teach a dwarf smith about “waifu tiers” (spoiler: he builds a golem wife and chaos ensues).

Campaign Kickoff

Here’s a starter: the Banestorm drops your players in the Nomad Lands—think Mad Max with horses and ogres. They’ve got nothing but their Earth gear (a dead phone, a half-eaten burrito), and their cheat powers kick in as they fend off a Reptile Man raid. From there, they trek to Cardiel to unravel the Banestorm’s resurgence—portals are spitting out vending machines and goblins, and someone’s got to stop it. Maybe the wizards of Araterre have answers, or maybe a shady Earth expat’s pulling strings.

GURPS Tweaks

• Advantages: Hand out a free Unusual Background (Banestorm Blessed) with perks like Magery 1, Gadgeteer (for tech hacks), or a cinematic Luck boost.
• Skills: Let them keep some modern skills, but give out extra points for these "useless" background skills, they might come in handy at some point... but don't bet on it. Otherwise look at skills that need to be learned fast, and ones that have lower TL equivalents.
• Tone: Go big and silly. GURPS can handle anime-style stunts—let them one-shot a troll if the dice say yes.

Why It Works

Yrth’s depth gives you room to flex—political intrigue in Megalos, wilderness survival in the Orclands, or culture clashes in Sahud. The isekai tropes add a layer of player-driven chaos that keeps it fresh. Plus, who doesn’t want to see a medieval knight react to a player yelling “Truck-kun got me here!”?