Oracle Text

Enchant creature

Enchanted creature gets -5/-0.

2U: Return Agoraphobia to its owner's hand.

Card Rulings

1/24/2013 Only Agoraphobia’s controller can activate its last ability, no matter who controls the creature Agoraphobia’s attached to.
1/24/2013 Agoraphobia’s last ability can be activated only while it’s on the battlefield.
1/24/2013 Players don’t have priority to cast spells and activate abilities between combat damage being assigned and being dealt. This means that if you want to return Agoraphobia to its owner’s hand before combat damage is dealt, you must do so before combat damage is assigned (and the creature will no longer get -5/-0).