Here is the full list of all 25 Pistol Whip trophies - there are 9 bronze, 8 silver, 7 gold and 1 platinum.
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Pistol Whip 1000 enemies
Finish Death without harming the dancers
Finish High Priestess with "Brawler" style on Hard
Pistol Whip every enemy on the bridge in R U Afraid on any difficulty
Finish any scene on Hard while using "Proper Legacy" (Pistol Deadeye) style
Earn an S rank or higher in any scene
Earn an accuracy rating of 90% or higher in any scene ("Classic" style only)
Kill all enemies in a scene without missing a shot ("Classic" style only)
Empty your entire clip without missing a beat ("Classic" style only)
Finish any scene on Hard ("Classic" style only)
Finish any scene on Normal ("Classic" style only)
Finish any scene with no armour remaining ("Classic" style only)
Finish any scene without hitting an enemy ("Classic" style only)
Finish any scene without taking damage ("Classic" style only)
Earn 5,000,000 points (cumulative per play)
Pistol Whip 10 or more enemies in a single run ("Classic" style only)
Pistol Whip an enemy when you have no armour ("Classic" style only)
Travel a total of 15 kilometers
Finish any scene with at least 3 modifiers active
Finish any scene on Hard while using "Dual Pistols" style
Kill a total of 1000 enemies on beat
Reload on beat 100 times
Finish any scene on Easy ("Classic" style only)
Complete the Basic Tutorial