This is a complete achievement walkthrough of The Fall on Xbox One. During this playthrough I unlock every achievement except for "Merciful" which is unlocked at the very end of the game. I explain how to get that achievement near the end.
Video Start Time -
31:58For this achievement you have to shoot the first fish in the lower labs area on your first shot. After you place the jar of sticky stuff onto the platform and push it into the water, you have one shot to hit the fish as it jumps out of the water.
According to comments you can Quit the software and start the game back up if you miss the achievement. As in terminating the whole game, not just going to the main menu.