Here is the full list of all 19 Unearned Bounty achievements.
Win a match
Kill another player
Kill 10 players in a match
Kill 100 players across all matches
Kill 1000 players across all matches
Kill 10 players without dying
Kill 5 players without dying
Kill 15 players without dying
Kill another player while their on a killing spree
Kill 2 players with the same cannon volley
Kill another player without ever seeing them
Kill 2 players within 15 seconds of eachother
Kill 3 players within 15 seconds of eachother
Kill 5 players within 15 seconds of eachother
Win 10 matches
Win 100 matches
Finish a round without dying
Win a round without dying
Win 1000 matches