Doorkeeper
Creature — Homunculus
Defender
, 
: Target player mills X cards, where X is the number of creatures you control with defender.
One piercing stare usually convinces thieves to go elsewhere.
Kev Walker
The List (PLST)
• #IMA-53Rulings
The number of creatures with defender you control is counted when the ability resolves.
(wotc • 2012-10-01)
Rulings
The number of creatures with defender you control is counted when the ability resolves.
(wotc • 2012-10-01)