Here is the full list of all 100 Star Saviors achievements.
Reach at least power level 8 in story mode
Destroy the evil UFO in story mode on easy or harder difficulty
Complete a stage with less than 10.00% hull remaining in story mode
Complete a stage with less than 5.00% hull remaining in story mode
Complete a stage with less than 2.50% hull remaining in story mode
Destroy a total of 20 000 enemies
Destroy a total of 50 000 enemies
Destroy a total of 100 000 enemies
Destroy a total of 250 000 enemies
Destroy a total of 10 000 enemies while in break mode
Destroy a total of 30 000 enemies while in break mode
Destroy a total of 90 000 enemies while in break mode
Destroy a total of 200 000 enemies while in break mode
Complete story mode on easy or harder difficulty
Complete story mode on normal or harder difficulty
Complete story mode on hard or insane difficulty
Complete story mode on insane difficulty
Complete survival mode on easy or harder difficulty
Complete survival mode on normal or harder difficulty
Complete survival mode on hard or insane difficulty
Complete survival mode on insane difficulty
Complete arcade mode on easy or harder difficulty
Complete arcade mode on normal or harder difficulty
Complete arcade mode on hard or insane difficulty
Complete arcade mode on insane difficulty
Complete survival mode on easy or harder difficulty without restarting any stage
Complete survival mode on normal or harder difficulty without restarting any stage
Complete survival mode on hard or insane difficulty without restarting any stage
Complete survival mode on insane difficulty without restarting any stage
Complete arcade mode on easy or harder difficulty without restarting any stage
Complete arcade mode on normal or harder difficulty without restarting any stage
Complete arcade mode on hard or insane difficulty without restarting any stage
Complete arcade mode on insane difficulty without restarting any stage
Get at least 20 000 000 points in story mode
Get at least 30 000 000 points in story mode
Get at least 45 000 000 points in story mode
Get at least 60 000 000 points in story mode
Destroy the evil UFO in story mode on normal or harder difficulty
Destroy the evil UFO in story mode on hard or insane difficulty
Destroy the evil UFO in story mode on insane difficulty
Get at least 5.00 average effective multiplier in story mode on normal or harder difficulty after completing all stages
Get at least 6.00 average effective multiplier in story mode on normal or harder difficulty after completing all stages
Get at least 7.00 average effective multiplier in story mode on normal or harder difficulty after completing all stages
Get at least 8.00 average effective multiplier in story mode on normal or harder difficulty after completing all stages
Complete a single mission with 100% hull remaining in story mode on easy difficulty
Complete a single mission with 100% hull remaining in story mode on normal difficulty
Complete a single mission with 100% hull remaining in story mode on hard difficulty
Complete a single mission with 100% hull remaining in story mode on insane difficulty
Reach at least power level 10 in story mode
Reach at least power level 13 in story mode
Reach at least power level 15 in story mode
Complete a stage with less than 1.00% hull remaining in story mode
Get at least 20 000 000 points in survival mode
Get at least 40 000 000 points in survival mode
Get at least 60 000 000 points in survival mode
Get at least 80 000 000 points in survival mode
Get at least 8.00 effective multiplier from a single stage in survival mode on normal or harder difficulty
Get at least 8.50 effective multiplier from a single stage in survival mode on normal or harder difficulty
Get at least 8.75 effective multiplier from a single stage in survival mode on normal or harder difficulty
Get at least 9.00 effective multiplier from a single stage in survival mode on normal or harder difficulty
Get at least 4 golden multipliers during a single game in survival mode on hard or insane difficulty
Get at least 8 golden multipliers during a single game in survival mode on hard or insane difficulty
Get at least 12 golden multipliers during a single game in survival mode on hard or insane difficulty
Get at least 15 golden multipliers during a single game in survival mode on hard or insane difficulty
Get at least 4 platinum multipliers during a single game in survival mode on normal or harder difficulty
Get at least 8 platinum multipliers during a single game in survival mode on normal or harder difficulty
Get at least 12 platinum multipliers during a single game in survival mode on normal or harder difficulty
Get at least 15 platinum multipliers during a single game in survival mode on normal or harder difficulty
Keep break mode up for 0.50 minutes during a non-boss stage in survival mode on normal or harder difficulty
Keep break mode up for 1.00 minutes during a non-boss stage in survival mode on normal or harder difficulty
Keep break mode up for 1.50 minutes during a non-boss stage in survival mode on normal or harder difficulty
Keep break mode up for 2.00 minutes during a non-boss stage in survival mode on normal or harder difficulty
Receive at least 75% repair bonus during a single game in survival mode on normal or harder difficulty
Receive at least 150% repair bonus during a single game in survival mode on normal or harder difficulty
Receive at least 250% repair bonus during a single game in survival mode on normal or harder difficulty
Receive at least 400% repair bonus during a single game in survival mode on normal or harder difficulty
Get at least 100 000 000 points in arcade mode
Get at least 250 000 000 points in arcade mode
Get at least 500 000 000 points in arcade mode
Get at least 999 999 999 points in arcade mode
Get at least 15.00 break multiplier at the end of a stage in arcade mode
Get at least 20.00 break multiplier at the end of a stage in arcade mode
Get at least 30.00 break multiplier at the end of a stage in arcade mode
Get at least 40.00 break multiplier at the end of a stage in arcade mode
Gain at least 4 no damage bonuses in arcade mode on normal or harder difficulty
Gain at least 8 no damage bonuses in arcade mode on normal or harder difficulty
Gain at least 12 no damage bonuses in arcade mode on normal or harder difficulty
Gain at least 15 no damage bonuses in arcade mode on normal or harder difficulty
Keep break mode up for 15 seconds during a non-boss stage in arcade mode
Keep break mode up for 25 seconds during a non-boss stage in arcade mode
Keep break mode up for 35 seconds during a non-boss stage in arcade mode
Keep break mode up for 50 seconds during a non-boss stage in arcade mode
Collect at least 2 000 000 value of items in a single stage
Collect at least 5 000 000 value of items in a single stage
Collect at least 10 000 000 value of items in a single stage
Collect at least 20 000 000 value of items in a single stage
Convert at least 2 extra shield to bonus points on normal or harder difficulty
Convert at least 4 extra shield to bonus points on normal or harder difficulty
Convert at least 7 extra shield to bonus points on normal or harder difficulty
Convert at least 10 extra shield to bonus points on normal or harder difficulty