Guest post by "Gunsolo" Here are a few suggestions.
William: Either "Thou. Art. Not. FUNNY!" or "Creatures of nightmare come forth. I fear thee not!!!" Mandrake: "Good luck" (from http://www.mysteriesofthearcana.com/index.php?action=comics&cid=49) Hunger Null Sword: "!GNAB" Royal Road: "Stand. Visualize. Demand."