Here is the full list of all 16 Black Legend trophies - there are 5 silver, 10 gold and 1 platinum.
Defeat Christiaan Huygens
Catalyze and enemy with 3 stacks of Crimson, Silver, Bronze and Gold in a single hit.
Earn all other trophies.
Pick Mephisto in the final battle.
Pick the Mercenaries in the final battle.
Defeat Grand Piers
Defeat Anthonie van Leeuwenhoeck
Defeat Benedict Baruch
Complete the "A Wedding in White" sidequest.
Complete the "A Song Stuck in my Head" sidequest.
Complete the "Down the Well" sidequest.
Fight and defeat every encounter at least once in a single playthrough.
Collected all weapons in the game.
Collected all armour sets (including every tier) in the game
Beat the game on Normal Difficulty or above without using a Quarter Tree.
Complete the game on the Hard Difficulty.