Gregorian vs Mouvelian

Please forgive my lack of comprehension on this subject, as I've read what I could find on the Mouvelian calendar used in Tyria but I could not find an answer to a question that arose as I was looking at how character ages are determined. From what I understand the calendar is on a strict 365-day year which makes calculating character ages simple, but when you compare this to the Gregorian calendar would this not result in an offset of a day between the two every four years?

I understand this offset would be minor at first, but after a little over a century wouldn't we be about a month off? This would mean seasons and holidays further and further apart- Halloween would not take place at the same time as Shadow of the Mad King, Christmas would not take place at the same time as Wintersday, etc. Granted, this game is not likely to be around a hundred years from now, but if we look at some earlier mmo's out there we have some around the 15-20 year mark that are still running. Such a difference here would have us off by 4 or 5 days already.

I know that one method of fixing this is as simple as the leap year in the Gregorian calendar. However, this would have to be factored into the age of our characters as well, and they would either no longer adhere to the strict 365 day birthday present, or their age would be misrepresented.

Am I missing something or overthinking it? Probably, which is why I'm asking what it is I can't seem to find that makes this calendar, the holidays/seasons, and the character aging system work together other than the simple explanation, "Because we say it does."

Thanks in advance for helping me make sense of this.

You're over-thinking it. It's one of those things where lore and mechanics don't always match up. In lore the Mouvelian Calendar is always exactly 365 days long, in practice it matches the Gregorian calendar exactly (including leap years, they're just not mentioned) for the sake of convenience.

Events will move, for example the Halloween event doesn't always start or end on the same day every year, but not because of the difference between the Mouvelian and Gregorian calendars - it's because Anet always does updates on a Tuesday and the days of the week don't match with months, and they will pick which Tuesday to start it on and how long it runs for based on their wider release schedule. So some years it starts earlier in October and ends just after real-life Halloween, sometimes it goes on further into November. Same with the other festivals.

The one exception is character birthdays. Those are on a strict 365 day cycle, probably because getting computers to cope with leap years is more hassle than it's worth for something that's relatively minor. So from 2016 onwards the birthday date for existing characters moved back 1 day (meaning the oldest characters get it on the 27th August). It is inaccurate but like I said probably not worth the hassle it would take to fix it. If the game runs for 20+ years it may start to look really strange, but if it bothers players it probably could be fixed.

Building on what Danikat said, ANet's made it clear that the passage of time in-game does not correspond to the passage of time in the real world (anymore). The most obvious example is the end of S2 and HoT- nine months passed between them in the real world, but in game, it was a matter of days, if not hours.

Halloween and Wintersday are almost exceptiond. Each one is a year apart from the last in-game and out-of-game, give or take a few days, so at those two points the calendars are effectively synched. As soon as the event ends, though, it's anyone's guess.

@Mooncutter.2907 said:From what I understand the calendar is on a strict 365-day year which makes calculating character ages simple, but when you compare this to the Gregorian calendar would this not result in an offset of a day between the two every four years?

The Gregorian calendar has an offset day every 4th year because a day in our world isn't actually 24 hours long. A day in our world is actually 23 hours, 59 minutes and 45 seconds long. If Tyria doesn't have this disparity, 365 days per year is precise/correct.

The years line up, but technically the Mouvelian calendar was 360 days, not 365. They "changed" this in an interview, but it seems they've since gone back on this because, quite frankly, their change was "oh we discovered the year is actually 365 days! - some asura" which makes no logical sense given that such a difference would be notable within a few years of the seasons no longer lining up. They've made no mention of this in-game, where the end-all-be-all lore is, and seems to have overall dropped this, but retained the "syncing of years" which was the original purposes of adding those 5 days.

Even the syncing of years doesn't make much sense, given that Wintersday happens on the Spring Equinox of Tyria (for us, this would be March 21st, give or take a day or two on some years). Meanwhile, Halloween is suggested to be the ides of autumn (making it 45 Scion in the Mouvelian calendar every year). Since there is obviously not a 135 day gap between Halloween and Wintersday, or even a 90 day gap for the entire of Colossus season to be, it's pretty obvious the only syncing that could occur without massive changes to festivities, would be the year number.

@"Konig Des Todes.2086" said:The years line up, but technically the Mouvelian calendar was 360 days, not 365. They "changed" this in an interview, but it seems they've since gone back on this because, quite frankly, their change was "oh we discovered the year is actually 365 days! - some asura"As I recall, and I can't find the character right now, but the asura says something like "we are generously adding 5 extra days to the calendar".

@Rognik.2579 said:

@"Konig Des Todes.2086" said:The years line up, but technically the Mouvelian calendar was 360 days, not 365. They "changed" this in an interview, but it seems they've since gone back on this because, quite frankly, their change was "oh we discovered the year is actually 365 days! - some asura"As I recall, and I can't find the character right now, but the asura says something like "we are generously adding 5 extra days to the calendar".

It was an interview (so it's in the whole "only semi-canon" argument they constantly use because they're worse at keeping track of what they say despite us documenting such), which has now since been taken down, but the quote is on the wiki:

Friends and fellows. Due to recent (amazing!) reasoning by scholars of the Astronomagical Society, we are pleased to announce that we have added the five hidden days to our calendar year! That's five extra days we've recognized for you to advance your work before the annual review. Gifts and gratitude are unnecessary. We merely acknowledged them officially; we did not create them. May all your projects be almost as successful as ours.

— Mikkhttps://wiki.guildwars2.com/wiki/Mouvelian_calendar

Either way though, 5 days becomes a full month in 6 years. Within a lifetime, you'll have winter when it should be summer and vice versa. And you can't just shorten the duration of a day to make it fit either. Whether this was a "correction to the calendar" or "hey we'll just do this because", it won't make sense, because the Mouvelian calendar is seasonal.

@Konig Des Todes.2086 I know that there is one character actually in game who talks about the calendar shift, and I think it's in Metrica Province, but I have no idea where now, and the devs have been saying that in-game sources trump anything said in interviews, past, present or future. It's when the game self-contradicts that we run into problems.

@"Rognik.2579" I have never seen nor heard of such an NPC. That quote and related interview, for as long as I've ever known, has been the only indication of the "added 5 days".