As the original Baldur's Gate games leak for Game Pass again, fans reminisce over the bizarre D&D systems that drove BioWare's CRPGs
Jan. 4, 2024Who remembers THAC0?
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The original Baldur’s Gate games appear to have leaked for Xbox Game Pass, causing players to reminisce about the bizarre rulesets of the D&D editions they were based on.
Unfortunately, while Baldur’s Gate 1 and 2 are classics for a reason, they’re not always the most accessible games.Baldur’s Gate 3is built on the Fifth Edition (5e) of Dungeons & Dragons, a system that might seem complicated from the outside, but is one of the more accessible versions of the TTRPG.
By contrast, the first two games in the series are based on Advanced Dungeons & Dragons' Second Edition, which feature the infamous THAC0 system. THAC0 - as explained by shellshocked Baldur’s Gate fans over onReddit- stands for ‘To Hit Armor Class 0’, and is a version of the hit chance and AC system that’s present in current forms of D&D that flips what you might expect from 5e on its head. In the modern game, the higher your Armor Class (AC), the better defended you are, and the less likely your enemies' attacks are to hit. THAC0 inverted that idea, meaning that a lower AC was actually better.
Realistically, that means that THAC0 isn’t actually that complicated - it’s a plus or minus system added to your enemies' rolls to determine whether they hit or not. The numbers are inverted from 5e, of course, but the only major way that the system differs is by directly affecting a roll - in 5e, AC essentially works by limiting your likelihood of rolling a successful hit, while THAC0 directly adds or subtracts from the number you roll.
Nevertheless, while THAC0 may not ruin the experience of Baldur’s Gate 1+2, there’s no doubt it’s a very different system, housed within a very different game. The first game just turned 25 years old, and if you’re used to Baldur’s Gate 3, you won’t find the same extent of player freedom here. If these games do end up on Game Pass and find themselves with a swathe of new players, it might be worth remembering that while these might be classics, that doesn’t necessarily mean that they’re easy to play in the modern day.
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I’m GamesRadar’s news editor, working with the team to deliver breaking news from across the industry. I started my journalistic career while getting my degree in English Literature at the University of Warwick, where I also worked as Games Editor on the student newspaper, The Boar. Since then, I’ve run the news sections at PCGamesN and Kotaku UK, and also regularly contributed to PC Gamer. As you might be able to tell, PC is my platform of choice, so you can regularly find me playing League of Legends or Steam’s latest indie hit.
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