Eradicator
Not unlocked yetKill 100 aliens.
First Blood
Not unlocked yetKill 1 alien.
Annihilator
Not unlocked yetKill 10,000 aliens.
Exterminator
Not unlocked yetKill 1000 aliens.
Xenocide
Not unlocked yetKill 50,000 aliens.
Field Promotion
Not unlocked yetEarn a silver (or better) medal.
Flawless Victory
Not unlocked yetEarn a Gold Medal.
Salvage Rights
Not unlocked yetKill an alien boss creature. (Juggernaut, Rumbler, Turtle, or Crasher)
Liquidator
Not unlocked yetSell 10 towers.
Surplus
Not unlocked yetWin a mission with at least 1,000 resources remaining.
Penny Pincher
Not unlocked yetWin a mission with at least 5,000 resources remaining.
Filthy Rich
Not unlocked yetWin a mission with at least 10,000 resources remaining.
Arsenal
Not unlocked yetBuild 20 towers of any type in one mission.
Full Defense
Not unlocked yetBuild 50 towers of any type in one mission.
Indecisive
Not unlocked yetSell 10 towers or more in a single mission.
Happy Returns
Not unlocked yetRecover a loose core.
Hey! That's mine!
Not unlocked yetKill an alien carrying a power core.
Yellow Beats Green
Not unlocked yetUpgrade a level 1 tower to a level 2 tower.
Retry
Not unlocked yetUse the Reload Checkpoint option.
If At First You Don't Succeed, Retry Again
Not unlocked yetUse the reload checkpoint option five times in a single mission.
Leadhead
Not unlocked yetBuild 100 Gun towers.
Burn Baby Burn
Not unlocked yetBuild 100 Inferno towers.
Pew Pew
Not unlocked yetBuild 100 Laser towers.
Not So Fast
Not unlocked yetBuild 100 Temporal towers.