I was playing Animal Crossing on DS the other day, which has many in-game holidays and events that occur on certain dates throughout the year. Lots of online games (especially MMOs) also have similar events. I was wondering if anyone could suggest any fun games (especially offline ones) that are either holiday-themed or have holiday/seasonal events. Last year I picked up Costume Quest, which wasn’t very long, but it had a lot of Halloween charm. Thanks!

Ahhh... Animal Crossing. The game that snuck up on me and bit me in the ass. Why I kept playing it; I don't know. Why I had a house full of shit that I kept picking up; I can't tell you. Why I kept running to the river and fishing; no fucking idea. And the list goes on...

Harvest Moon/Rune Factory games have ingame holidays on the ingame calendar, Gurumin has a lot of costumes and stuff if you play it on a holiday (christmas, new years etc.).

TES II Daggerfall has a lot of in-game holidays too, but there isn't really any holiday-theme there

In Bully (PS2/Wii/360) you go through Halloween and Christmas. It's from Rockstar and has a GTA feel. Less difficult and a lot of fun.

I came in thinking Animal Crossing and Harvest Moon, but you guys covered those.

Batman: Arkham City has a bit with Calendar Man. If you visit him on certain RL days of the year, you get different stories. There's an achievement for visiting him 12 times (can be worked around by altering the clock and being offline).

Dunno about offline ones, but WoW has some nice holidays / events.

I second Harvest Moon, that series is pretty good and does have a larger emphasis on holidays than most games.

You might also like the Merry Gear Solid 2 fangame.

Guild Wars

Dungeon Keeper gives you special messages on several holidays, and there are some levels that only show up during a full moon.

Crimsonland snows if you play it during Christmas. I think it may have several others.

Team Fortress makes a big deal of this, with special events and items that work only on certain days.

Nethack behaves differently depending on the phase of the moon while you're playing.

If you play Defcon on Christmas then Santa flies across the map.

Try playing Tyrrian 2000 (one of the free games here) around Christmas. It changes some of the game's graphics.

Cave Story+ also changes some graphics during holidays.

Raptor adds some extra stuff on certain dates (designer birthdays mostly) like monkeys and cows that shoot guns at you. You can enable them at other times if you want the extra cash from the baddies, but the bonus enemies are pretty tough.

Infectonator: Christmas Edition
http://www.kongregate.com/games/TogeProductions/infectonator-christmas-edition?acomplete=infecton
Not offline, unless you find a way to download the .swf file. I love going through the games in this series every now and then.

Also, I think Rise of the Triad changes the character's pictures on the loading screen on certain holidays.

Cave Story +
If you play it on X-Mas ALL the game world,including bosses, are different!
Also your character wear a santa hat