YMMV / Oko Yrrhedesa

• Enjoy the Story, Skip the Game: The Yarra, River of Death scenario has been used in Poland by people playing a wide variety of games, usually with just minimal changes to its mechanics, being a really well-received and newbie-friendly module that's almost entirely setting- and game-agnostic. There are people who don't even know it was taken from another game, yet played it extensively using bunch of other Polish TTRPGs, WFRP, Fate, Savage Worlds and many more.
• Popular Game Variant:
  • The game was designed for d6 almost exclusively, yet it does use d10 for heavy weapons and casting spells. A popular replacement for the hard-to-come-by (at least when the game came out) d10 dice was a 2d6-1 roll, and -2 if the outcome was 12. While not perfect (it still gets affected by the bell curve), it was deemed "good enough" in gaming circles of the era. Nowadays, it's mostly a historical curio and, at best, a solution for people who somehow stumbled into the game and trying their hand at the whole tabletop RPG thing for the first time, lacking gaming resources.
  • There were a few different homebrew rules for governing the carry capacity of players circulating the gaming scene. The most popular one abstracted things, rather than trying to keep their measurable weight, offering a slot-like system based on Strength of the PC. Each point offered a slot that either allowed to carry something heavy, 2 medium objects^note This way, a heavy weapon and a combination of sword and shield "weighted" the same or 4 trinkets. With 7 being the lowest possible value of Strength, it offered more carry than it was usually needed, prevented excessive hoarding, and made the maximum possible starting gear neatly fit into 2 slots^note Helmet, shield, regular weapon, some light armour or helmet, heavy weapon and light armour. Most importantly, nobody had to bother with tedious weight evaluation and calculations.
• Scrappy Mechanic: The game suffers from a THAC0-like counterintuitive system for difficulty modifiers. The game operates as a roll-under. Any sort of negative modifier increases difficulty and is marked with a "+"... while in practise it decreases the stat you have to roll. Correspondingly, positive modifiers increase the stat in question, despite being noted with a "-". Pretty much everyone who ever ran the game switched the notations to be more intuitive. To make things even weirder, the modifiers the gear might come with are handled normally, so you can end up with stuff like "+4" difficulty for shooting your bow in the total darkness of a dungeon, but also a +1 bonus from the fact it's an enchanted weapon, ending up with having to subtract -3 from your Dexterity when making the roll.
• Scrappy Weapon: Light crossbows. They deal pitiful d3 damage, where every other ranged weapon does d6 at the bare minimum. To its credit, the game doesn't even list them as typical equipment and only mentions them as possible loot from certain small-sized enemies, like goblins and kobolds.
• Serial Numbers Filed Off: For all intents and purposes, Yarra, River of Death is The African Queen in fantasy land. Variety of plot elements and even directly lifted scenes^note Two sets of dangerous rapids, the second leading to The Great Repair moment, a huge marshland with tall reeds and no way out, a prudish lady that gets easier on the skipper as the adventure progresses, a close encounter with enemy fortification, another marsh full of leeches just waiting to crawl over anyone who gets into water, etc. match almost 1:1. The main difference comes in the form of the ultimate goal of the adventure and that it kind of trails off in the final phase, after reaching the huge lake (where the film ended). Tropes Are Tools, since the scenario is still one of the most iconic modules ever published in Poland and going through it was even a sort of hazing ritual for the new players. What makes it further stand out is that it manages to adopt the film's plot without the typical issues of adopting non-interactive media into a game format.

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