HISTORY
THAC0 (To Hit Armor Class 0) “To Hit Armor Class 0” was a game mechanic used in the Advanced Dungeons & Dragons (AD&D) game system, which was a more complex and detailed version of the original Dungeons & Dragons (D&D) game. THAC0 was not used in the Basic D&D game system, which was designed to be simpler and more accessible to new players.
In Basic D&D, players roll a d20 and add their attack bonus to the roll. If the total is equal or greater than the target’s AC, a hit is made. This system is similar to the one used in the 3rd edition of D&D where THAC0 was removed.
In versions of D&D prior to the 3rd edition, armor class (AC) was represented by a number that represented how difficult it was to hit a character or creature. A lower AC number meant that it was easier to hit the character or creature, while a higher AC number meant that it was more difficult to hit them.
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THAC0 is a value that represents a character’s or creature’s ability to hit a target with an armor class of 0. The lower the THAC0 value, the better the character or creature is at hitting targets with an AC of 0. To determine if a character or creature hits a target with a different AC value, you would subtract the target’s AC from the character or creature’s THAC0 value and consult a table that lists the result as a percentage chance of hitting the target.
For example, if a character has a THAC0 of 20 and is attacking a target with an AC of 4, you would subtract 4 from 20 (20-4=16) and consult a table that would tell you that the character has a 75% chance of hitting the target.
THAC0 was replaced by the more simple and intuitive “roll-over” system in the 3rd edition of D&D, where a player roll a d20 and add his/her attack bonus, and if the result is equal or greater than the target’s AC, a hit is made.
RECEPTION
THAC0 was generally well-received by players of the game when it was first introduced. Many players found that the system added an additional layer of complexity and realism to the game, and appreciated the ability to fine-tune their characters’ abilities to hit targets with different armor classes.
However, as the game’s community evolved, some players found the THAC0 system to be confusing, difficult to use and prone to errors. It was not uncommon for players to make mistakes when calculating their chances to hit, or to accidentally use the wrong column of the THAC0 table.
Overall, THAC0 was a controversial game mechanic, some players enjoyed it for the added realism and complexity it brought, while others found it confusing and difficult to use.
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CONTROVERSY
In September of 2021, Wizards of the Coast released their newest module, “The Wild Beyond the Witchlight“. Within it, starred a grumpy old clown named, you guessed it, “THAC0”. Being a gatekeeper of sorts within the story, many took this as an offensive joke/poke towards older players. ( Even though this author has NEVER met an older player “gatekeeper” that would not allow others to play for whatever reason )
Wizards however, said old grumpy THAC0 was simply a nod to an old AD&D gaming mechanic.
WHAT SAY YOU?