Here is the full list of all 27 The Last Day Defense achievements.
Complete all levels of the table First Contact with 5 stars
Complete all levels of the table First Contact with 5 stars on Hell difficulty
Complete all levels of the table Sunny Expanse with 5 stars
Complete all levels of the table Sunny Expanse with 5 stars on Hell difficulty
Complete all levels of the table Valley of Thunder with 5 stars
Complete all levels of the table Valley of Thunder with 5 stars on Hell difficulty
Complete all levels of the table Top of the World with 5 stars
Complete all levels of the table Top of the World with 5 stars on Hell difficulty
Completely upgrade all the towers on a level on Hell difficulty
Complete a level without tower modules on Hell difficulty
Destroy 100 MiniTechs
Destroy 1000 MiniTechs
Destroy 10000 MiniTechs
Destroy 100 Heavy Fire Tanks
Destroy 1000 Heavy Fire Tanks
Destroy 10000 Heavy Fire Tanks
Destroy 100 Air Bombers
Destroy 1000 Air Bombers
Destroy 10000 Air Bombers
Destroy 10000 enemies
Destroy 50000 enemies
Destroy 100000 enemies
Complete all levels of the table Frozen City with 5 stars
Complete all levels of the table Frozen City with 5 stars on Hell difficulty
Find all the shadows of the past
Hear all the voices of the past