Here is the full list of all 24 Gunkid 99 achievements.
Unlock 16 or more guns.
Score 100 points or more in NORMAL MODE in any World-1 stage.
Attain a new High-score with Zero-Baggage equipped.
Score 100 points or more in EQUIPPED MODE in any World-1 stage.
Survive for 6 or more minutes in a single round.
Survive for 3 or more minutes on a single Health.
You beat the Game!
Score 100 points or more in EQUIPPED MODE in any World-2 stage.
Score 100 points or more in NORMAL MODE in any World-2 stage.
Score 100 points or more in EQUIPPED MODE in any World-3 stage.
Score 100 points or more in NORMAL MODE in any World-3 stage.
Score 100 points or more in EQUIPPED MODE in any World-4 stage.
Score 100 points or more in NORMAL MODE in any World-4 stage.
Score 100 points or more in EQUIPPED MODE in any World-5 stage.
Score 100 points or more in NORMAL MODE in any World-5 stage.
Score 200 points or more in EQUIPPED MODE in ANY stage.
Score 200 points or more in NORMAL MODE in ANY stage.
Survive for 10 or more minutes in a single round.
Bought 20 or more items.
Earn 100 or more Coins in a single round.