BioShock Infinite
80 Achievements
1,695
42-52h
Dead Drop
On three occasions, knocked out an enemy after silently dropping off a Freight Hook.
10
How to unlock the Dead Drop achievement in BioShock Infinite - Definitive Guide
In this area there are loads of Skyhooks and will be using them for the achievement. Unlock the regular game you can not launch yourself into an enemy and attack them. You will instead need to land behind them and subtly sneak up behind them and knock them out. The Peeping Tom Plasmid will be very useful since you don't have much time between landing and knocking out the enemy. Each knock out will show a counter on your screen and restarting the checkpoint does not reset your counter.
A female Splicer will be seen sitting at the first chandelier. Land behind her, use Peeping Tom. She will "notice" you (she goes yellow) but you can knock her out.
Reload 2 more times and the achievement will be yours!
This is best gotten in the Service Bay area where you are looking for the CO2 scrubber. There are plenty of enemies and Freight Hooks in the area to make this trophy easy here. You need to attach to a Freight Hook by pressing , then land silently behind an enemy by pressing to detach from the Freight Hook and holding upon landing to land silently. You then have to knock them out from behind with . The best way to do this is to land silently behind an enemy and use Peeping Tom by holding so the enemy doesn't see you. You can then easily go up behind them and press to knock them out without getting caught. Do this 3 times and you will get the trophy.
Here is a video description by WORLDEATER1 for the trophy: