Here is the full list of all 77 Revenge of the Titans achievements.
Turned 100 3-D Titans into 2-D Titans
Squished 50 Titans under new buildings
Crushed 25 Titans under new buildings
Repaired your buildings 5 times
Used bezerk powerup 5 times
Researched all weapons
Giant Titan killed within a few metres of the base
Used the freeze powerup 5 times
Lost 25 buildings to the enemy
Used the shield powerup 5 times
Vanquished 2,500 Titans
Nuked 100 Titans from orbit
Nuked the site from orbit 5 times
Researched all turret upgrades
Researched the droid factory
Researched all explosive tech
Researched nuclear reactors
Researched all defenses
Researched the decoy tower
Lost 10 buildings to the enemy
Completed the Moon missions
New rank: brigadier
Destroyed a Leviathan
Base held together with tape and string at end of mission
Vanquished 1,000 Titans
Got $10,000 in the bank
New rank: lieutenant colonel
New rank: colonel
Completed the Earth missions
Completed whole world at maximum difficulty
New rank: major
Defeated a Megatitan
Vanquished 500 Titans
New rank: captain
Nuked 50 Titans from orbit
Vanquished 250 Titans
New rank: lieutenant
Vanquished 100 Titans
Got $5,000 in the bank
New rank: second lieutenant
New rank: warrant Officer
Destroyed a Gargantuan
Destroyed a Behemoth
Destroyed the Ultratitan!
Completed the Mars missions
Completed the Saturn missions
Completed the Titan missions
Completed all missions at maximum difficulty
Lost 50 buildings to the enemy
Lost 100 buildings to the enemy
Vanquished 5,000 Titans
Vanquished 10,000 Titans
Fried 100 Titans with the Capacitor
Fried 250 Titans with the Capacitor
Fried 500 Titans with the Capacitor
Nuked 250 Titans from orbit
Blew up 100 Titans using explosives
Blew up 250 Titans using explosives
Blew up 500 Titans using explosives
Researched all science and technology
Researched everything
Lost 90% of your buildings to the enemy
Fully upgraded a turret
Made $5,000 profit from one mission
Made $10,000 profit from one mission
Made $15,000 profit from one mission
Got $25,000 in the bank
Got $50,000 in the bank
New rank: major general
New rank: lieutenant general
New rank: general
New rank: field marshal
Defeated 1 Xmas Ultrayeti
Defeated 2 Xmas Ultrayetis
Defeated 3 Xmas Ultrayetis
Defeated 4 Xmas Ultrayetis
Hurrah! Christmas is finally over!