Deadly Haystack Trophy in Assassin's Creed III: Liberation
Kill 50 enemies from haystacks using the Blowpipe
How to unlock Deadly Haystack
The Blowpipe is the weapon both the Assassin and Slave Persona use to fire poisonous darts. This trophy requires you to murder 50 enemies with this weapon, whilst hiding in hay. You'll most likely have to grind this, so just find some haystacks in New Orleans and keep killing guards with the blowpipe.
I have added several pics to give you a simple but effective grinding way. You can get about 10 Blowpipe kills each time and you can keep doing this, since the first enemies will be respawned once you deal with the last. Pics below:
The last two guys in the last picture doesn't always work the 1st time. You may have to enter_exit the haystack a few times until you can lock on the closest enemy. Once that happens, the second guy will move a bit closer (to the first enemy's corpse) and you should be able to kill him as well.