Here is the full list of all 64 King Arthur's Gold achievements.
Return your team's flag 5 times
Test the air-speed velocity of a laden chicken
Get 5000 kills
Get killed with a pickaxe 20 times
Kill the enemy flag carrier 10 times
Use all animals in game
Sushi!
Kill 3 people with 1 bomb
Get 50 stomp kills
Kill an enemy with a tamed shark
Get a kill with each class in the same round
Get 500 kills
Capture 5 warboats
Ride in every vehicle
Cap 20 flags
Reach 500 coins at a time
Cap 5 flags
Catapult a shark
Get 5 kills with the drill
Kill someone using a fire arrow
Get launched from a catapult 20 times
Kill a player with a boulder 5 times
Get a bomb kill as an archer or builder
Get a kill by launching a boulder from a catapult
Run over an enemy with a vehicle
Use fire ammo 20 times
Use water arrows 20 times
Carry all 4 kinds of arrows
Complete 10 Challenge mode maps
Take 40 halls
Save the Princess
Kill the Princess
Kill whole enemy team in TDM (at least 3 players)
Buy something at an enemy shop
Go down with a sinking warboat
Launch another player from a catapult 20 times
Carry 4 burgers in your backpack at a time
Eat a flower
Win 100 matches
Get killed with an arrow 20 times
Heal an ally with a burger
Take 10 halls
Man them!
Get 50 kills
Remain the last player alive in a TDM match
Get a kill while on fire
Win 10 matches
Get a kill on an enemy while dead
Get killed with a sword 20 times
Blow yourself up as well as the enemy using a bomb
Defuse a mine
Make love, not war
Steal an enemy's mine
Ride your tamed bison
Take a nap in a quarters
Join a modded server
Win a match
Use chat
Switch teams
Design and arrange a shrub
Commit suicide
Join multiplayer
Kill 5 enemies with 1 keg
Return your team's flag 20 times