A sense of humor, the ability to take fandom and fan doings lightly and in stride. In The Enchanted Duplicator, the Spirit of Fandom gives Jophan the Shield of Humor to protect him on the way to Trufandom, saying, "Then take this shield, which is called Umor. If you polish it every day and keep it shining it will protect you from many dangers."
According to Eve Harvey, who wrote notes on the text of the Seacon '79 Fan Room edition of The Enchanted Duplicator, "As a fan, a sense of humour is your best defence against the slings and arrows of the critics of your fanzine. Fans without this soon get hurt as they begin to take their fanac too seriously. It is an invaluable ingredient of the Perfect Fanzine."