Oddworld: Stranger's Wrath HD

Missable!
As you walk through New Yolk City after capturing X’plosives, before you reach the Bounty Store you will walk past a Clakker talking about a black market. The Clakker is standing to your left opposite a rope. Talk to her and she will give you the password.

Climb the rope and follow the path on top of the building until you come to a set of doors. Press to try and enter, again when asked for the password and then enter. The trophy will pop soon after, so head inside to have a look at some of the goodies on offer.

See the video below for a walkthrough. Credit to kamijordan.