A post in which your character encounters their fear(s). - well this is loaded but there you have it
A post in which your character has been given an undesirable gift. - Phyr threw a book at his head, does that count?
A post in which your character is clearly the protagonist. - he's the groom, it's his wedding day, that's fairly protangonist-y
A post in which your character may very well be the antagonist. - Oz refuses to help his sisters with their predicament, and also makes fun of them.
A post where your character is at the mercy of nature. - Oz and Phyri slog through a bog
A post in a thread set before 1890 - Oz in 1887 preparing to get married
A letter (to a played character) in which your character apologizes for something they've done. "Sorry you're not here," Oz says to his wife, after pointedly not inviting her and then asking someone else to come with him instead
A letter (to a played character) in which your character divulges a secret. the secret is he stole Endymion's coat because even given a month's notice he still waited until the day before leaving to pack
A post where your character makes a notable, but not life-threatening, error. Oz monologues his way into a corner
A post that is twelve words long. - yo Oz perpetually has too much to say to have these kinds of limitations placed on him
A post joining a lonely thread. - classist Oz (normal Oz) w/ Clifford
A starter for your very own lonely thread. Oz turns detective in this badly written murder mystery
A post, generally. - mistress things