Here is the full list of all 36 Full Metal Furies achievements.
Complete the game (true end) on NG+
Unlock every piece of equipment for every Class
Unlock every item in the Treasury
See the World
Defeat Titan King Prometheus
Make a choice
Enter the Cave
Solve the Last Puzzle
I always wanted a sibling
Unlock Cerby
Find All Monolith Stones in the Stygian Well
Solve the Fourth Puzzle
Solve the Fifth Puzzle
Solve the Second Puzzle
Solve the First Puzzle
Solve the Third Puzzle
Find all Monolith Stones in the Desert of Atlantis
Find and translate all Monolith Stones in the Foloi Forest
Find and translate all Monolith Stones in Thessaly
Find all Monolith Stones in Tartarus
Crack the code for at least 1 Computer
Appease Ferryman Charon
Complete all Class challenges
Destroy the World
Defeat Planetar Cronus
Defeat Sky Sniper Lelantos
Have 1 point in every skill for 1 Class
Air crit an enemy 5 times in a row
Master a piece of equipment by reaching its max level
The synopsis looks grim
Defeat Land Fortress Coeus
Defeat Wavebreaker Meneotius
Earn 1 level in your equipment
Unlock your first piece of equipment
Unlock Go-Cat
Find your first Monolith Stone