Here is the full list of all 18 抵御者 Defender achievements.
Cleared Level1Hard
Cleared Level2Hard
Cleared Level3Hard
Cleared Level4Hard
Complete all combos in Level1Hard
Complete all combos in Level2Hard
Complete all combos in Level3Hard
Complete all combos in Level4Hard
Clear Level1Hard without taking any damage
Clear Level2Hard without taking any damage
Clear Level3Hard without taking any damage
Clear Level4Hard without taking any damage
Clear all easy difficulty levels
Clear all medium difficulty levels
Survive in the InfiniteLevel for 50 seconds
Survive in the InfiniteLevel for 80 seconds
Survive in the InfiniteLevel for 110 seconds
Clear all hard difficulty levels