Here is the full list of all 9 Dick Wilde trophies - there are 3 bronze, 5 silver and 1 gold.
Defeat the Turtle Boss in the Swamp on Normal Difficulty
Defeat the Turtle Boss in the Swamp on Hard Difficulty
Defeat the Turtle Boss in the Swamp on Hardcore Difficulty
Defeat the Turtle Boss in the Lagoon on Normal Difficulty
Defeat the Turtle Boss in the Lagoon on Hard Difficulty
Defeat the Turtle Boss in the Lagoon on Hardcore Difficulty
Defeat the Turtle Boss in the North on Normal Difficulty
Defeat the Turtle Boss in the North on Hard Difficulty
Defeat the Turtle Boss in the North on Hardcore Difficulty