Here is the full list of all 12 Nelson Tethers: Puzzle Agent trophies - there are 7 bronze, 4 silver and 1 gold.
Closed the case with the rank of "Puzzle Agent."
Completed the case without chewing a piece of gum.
Completed the case and saw into the maw of madness.
Agent, you never submitted a wrong answer.
Complete every puzzle in Scoggins.
Thwarted Sheriff Bahg.
Took a transdimensional space voyage.
Helped Steve with his shipping problems.
Overcame your fear of Scoggins' hidden people and stay on the case.
Talked to Scruffman after seeing the unseeable outside of the diner.
Check into Valda's Inn
Submitted a successful puzzle answer on the first try while in the field.