To kill a snowy owl

[Rock of the Fraternity]

Considering his years of involvement in the Fraternity of Shadows, who knows what else he's gotten up to in a long and fruitful life, and the simple fact that he's a prominent figure living in the Demiplane of Dread, it is surely not inconceivable that someone, sometime, might try to bump off Balfour De Casteelle, president of the University of Dementlieu.

So if it were you, how would you go about it? Assume you have access to what is publically known about De Casteelle. If you had a reason to want to kill him, how would you go about it? Would you assemble a team, or make it a solo mission? What technique would you employ? Poison, magic, steel, strangulation? Where and when would you strike?

And for a bonus question, what kind of build would you find optimal to defeat Balfour, given all the information available in Van Richten's Arsenal? (But not the information on the FoS prestige class provided in Quoth the Raven articles; we want to keep some things surprising, don't we? )