ArcheAge. Yes, there really is a quest in Anvilton that requires you to go around and fill your bag with yata manure, yatas being those floppy-eared rabbit/kangaroo mount things.
As if stuffing crap in my quest bag wasn't enough, there's an occasional overpowering stench status effect that causes my character to temporarily pass out and fall down. Finally, the end of the quest required me to deposit a huge helping of poo on an NPC's workbench, complete with buzzing fly and rising steam animations.
How about you, Massively readers? What's the grossest quest you've ever done?
Every morning, the Massively bloggers probe the minds of their readers with deep, thought-provoking questions about that most serious of topics: massively online gaming. We crave your opinions, so grab your caffeinated beverage of choice and chime in on today's Daily Grind!