Full list of all 22 West of Dead achievements worth 1,000 gamerscore. It takes around 20-25 hours to unlock all of the achievements on Xbox One.
Helped 20 lost souls
Banished Injustice
Defeated 20 Outlaws
Completed the Canyon
Defeated Injustice (Preacher III)
Found the third rune
Completed the Church
Completed the Bayou
Completed the Graveyard
Defeated 5 Outlaws
Found the second rune
Defeated the Preacher (II)
Completed the Town
Found the first rune
Helped 5 lost souls
Defeated first Outlaw
Helped first lost soul
Completed the Farm
Defeated the Preacher (I)
Completed the Mines
Completed the Hunt
Completed the Crypt