Tiny Troopers

This achievement requires that you get a cumulative total of 50 kills with the machine gunner trooper across all plays and replays of all missions. The machine gunner is a special trooper that can be added before the start of the mission. He costs $50,000 CP per mission and isn't available until Mission 17. 

If you use the machine gunner several times in campaign, you may unlock this before completing the game. Otherwise, you can load up Level 23, purchase the machine gunner, and kill as many enemies as possible. Repeat the level, if necessary (purchasing the Machine Gunner each time), until unlocking the achievement. 

This achievement requires that you get a cumulative total of 50 kills with the machine gunner trooper across all plays and replays of all missions. The machine gunner is a special trooper that can be added before the start of the mission. He costs 50,000 CP per mission and isnt available until Mission 17. 

If you use the machine gunner several times in campaign, you may unlock this before completing the game. Otherwise, you can load up Level 23, purchase the Machine Gunner, and kill as many enemies as possible. Repeat the level, if necessary (purchasing the Machine Gunner each time), until unlocking the achievement.