Board Thread:General Discussion/@comment-29456315-20161206081120/@comment-27701762-20161206082934

Okay...but that doesn't work. Yes, the Roman numeral X is 10, but Roman numerals are not combined with Arabic numerals as with 201X. In those circumstances, the X has always signified a number between 0 and 9 (a two-digit number would be represented as XX, although 201XX would imply a date nearly 18,000 years in the future). That X is not and never has been added to the numbers in front. Given that the game was released in 2015, and perhaps the most important influence on the game was Earthbound, which was released in 1994 and featured that same X (i.e. the game takes place in 199X), the 201X in Undertale unquestionably represents a year between 2010 and 2019 (2020 would not be possible, as that would need to be represented as 202X).

Nothing suggests that Chara and Frisk fell in the same year. In fact, every piece of evidence statest that a good deal of time has passed between Chara's death and Frisk's entrance in the Underground. Meanwhile, 201X is the year that Chara fell into the Underground, and there is no actual suggestion that 201X also represents the year or range of years when Frisk fell in. By nearly all accounts the one thing we almost definitely know is that the events of Undertale do not take place in 201X.