Enable a Tower Augmentation Item on 10 Towers.
Earn a Gold medal in a Coordinated Defense Multiplayer Mission.
Earn a silver medal (or better) on all missions in the Story mode.
Complete the single player campaign in Story Mode.
Use the Core Teleport special weapon (Professor Taylor).
Use the Precision Targeting Special Weapon (Rear Admiral Phillips).
Using only Gun towers, Win any chapter 4 (or later) mission.
Using only Cannon towers, Win any chapter 4 (or later) mission.
Using only Inferno towers, Win any chapter 4 (or later) mission.
Using only level 1 towers, Win any Chapter 4 (or later) mission.
Use the command shuttle to move 6 map sections in Mission 6.
Build every tower and every upgrade for each tower.
Build and fully upgrade each tower type in one mission.
Win a chapter 4 (or later) mission with level 3 towers only and no selling.
Win a Gold medal on mission 19 without using the Command Shuttle.
Use the Temporal Cannon Special Weapon (Colonel Rissler).
Beat a Chapter 4 mission or higher with zero cores captured.
Use the Tower Overcharge Special Weapon (Advisor Zacara).
Use the Resource Reinforcement Special Weapon (Professor Briel).
Enable a Tower Augmentation item on any tower.
Survive 100 waves on any Super Grinder challenge mode.
Kill an alien boss creature. (Juggernaut, Rumbler, Turtle, or Crasher)
Use the reload checkpoint option five times in a single mission.
Survive 100 waves on Grinder challenge mode on any mission.
Save a core that is less than 10 seconds away from the map's exit point.
Use the Orbital Laser Special Weapon (General Cai).
Win a mission with at least 5,000 resources remaining.
Win a mission with at least 10,000 resources remaining.
Earn a Bronze (or better) medal in a Single Player Mission.
Use the speed up control for a total of 60 seconds in any mission.