Quick answer
Use a normal creature, lower it to finishing health, create open space, complete one full 360-degree turn and fire without using the scope. The unscoped shot after the turn must kill the creature.
Recommended setup
- Choose an ordinary isolated creature, not a boss.
- Use a weapon whose final damage you understand.
- Remove nearby hazards and ask co-op players not to attack.
- Leave enough room to turn without colliding with the target or terrain.
Exact attempt sequence
- Damage the target until one controlled shot should finish it.
- Stop firing and move to open ground.
- Centre the target before starting the turn so it is easier to reacquire.
- Rotate a complete 360 degrees.
- Do not aim through the scope.
- Fire the finishing shot immediately after completing the turn.
- Wait for the achievement notification before starting another target.
If it does not unlock
Check these conditions one at a time:
- Did the rotation complete before the shot?
- Was the killing shot definitely unscoped?
- Did that shot kill the creature rather than leave it alive?
- Did another player, fire or delayed effect deal the final damage?
- Was there a long pause between the rotation and shot?
Retry on the same type of weak creature. Do not move immediately to a boss or change every variable.
Easier practice progression
First complete direct kills reliably, then add a full turn without worrying about speed, and only then combine the turn with the unscoped finishing shot. The Trick Shots and Killscore guide explains how to isolate the target and control the final hit.
Sources
- How to Fish Global Achievements — Steam Community / Valve — https://steamcommunity.com/stats/4001890/achievements/?l=english — official achievement name and requirement.
- How to Fish General Discussions — Steam Community / Valve — https://steamcommunity.com/app/4001890/discussions/ — current player troubleshooting questions.