Day of the Dead
Go to your home city or a neutral city. Find its graveyard. Find Catrina. Dance with her.
Buy the ingredients for Bread of the Dead: 1 simple flour from cooking vendor, 1 ice cold milk from an innkeeper. Buy recipe in the graveyard and cook it at the graveyard fire (requires graveyard fire specifically). Then buy an [Orange Marigold] from the graveyard vendor. Once you have the bread, use the marigold in the graveyard, look for the one spirit with a !, and accept/turn in the bread quest.
You will receive one fake pet (bag space item) and an achievement from this.
I totally thought a guy in the costume didn't have real gear on in WSG and asked him to change.
If that wasn't dumb enough, it took me 2 more hours to realize we had a new holiday on hand.
And I almost missed it! Stupid Hyacinth Macaw farming. /grumble