This achievement requires you to get 100% completion.
Here is a list to attain 100% completion:
- Complete all 19 missions.
- Complete all 4 stranger missions in Tall Trees, MacFarlane's Ranch, Armadillo and Casa Madrugada.
- Save all 16 survivors (Lost Souls) which can be found at El Presidio (6) and at Fort Mercer (10).
- Complete all 4 challenges, in which you must attain rank 5 in each challenge, link to the guide:
- Obtain every outfit, this will come over time as you complete challenges.
- Break the Unicorn:
- Kill the Chupacabra: Undead Hunter challenge 5. The Chupacabra is quite small, black hound-like creature which will be marked on your map. 2 shots in the head will kill it.
Possible locations: South of Perdido, South of Sepulcro, Casa Madrugada and Northern Diez Coronaz.
- Have every territory saved once.
- Clear out all graveyards once, which will come as you complete story missions.