Just get the following items 

Unlockable                          How to unlock
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Turkey tail feathers             - defeat turdraken
turkey head                      - defeat turdraken
water draconian wings            - defeat water draconian
water draconian sword            - defeat water draconian
templar helm of light            - defeat red dragon
phoenix blade                    - defeat red dragon
inquisitor captain short polearm - defeat the captain at citadel
inquisitor's guard helm          - defeat the guards at citadel
Elemental rock hammer            - defeat the rock elemental
inquisitor guard's spear         - defeat the guards at citadel
Soul scythe                      - defeat soulseeker