Foe Sirvente is a merit song Bards at level 75 in Final Fantasy XI. It is a tier two skill that can be initially purchased for 3 points, and then upgraded twice for 4 and then 5 points.
Foe Sirvente is a single target song. The affected player character will lose enmity at a decreased rate than normal. This song is used to help the tank keep the attention of the enemy creature.