War on Drugs (Virgil)
Take out drug trucks and drug boats to complete this mission. Note that these vehicles don't have be in Faith's region to count for the kill.
Despite the lack of hostiles in the post-game, this mission can still be completed after Joseph has been defeated. Just keep looking for vehicles with the 'destroy' icon.
Kill five trucks and five boats to wrap this one up.
Completing this mission also buffs your Ultimate Hunter homeopathic.