Here is the full list of all 50 Flood of Light achievements.
Check out the producer list
Gain a S stage glory on 7F
Gain a S stage glory on 8F
First time to replay completed chapter
Activate the Thunder Prop
Take or move light over 1000 times
Complete 50% game progress
Activate the Wind Prop
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Extract the power from The Code of Sea
Back to the game again
Activate the Fire Prop
Take or move light over 666 times
Activate the Marsh Prop
Take or move light over 300 times
Complete levels without closing tips
Take lights from three different lamp posts
Fix ALL Robot
Activate the Land Prop
Take lights from two different lamp posts
Fix the first Robot you met
Activate the Sky Prop
Collect a letter marked 01
Pass through a huge advertisement board on 7F
The first time you submerged in water
First time to replay the level
Check the telescope at Elevator
Extract the power from The Code of Light
Choose keyboard control on pause page
Activate the Water Prop
Activate the Mountain Prop
Extract the power from The Code of Spirit
Acquire all Wicks
Complete RainDay with the 'Sunshine' Ending
Complete RainDay with the 'Regression' Ending
Restart the game after completed the Ending
Gain a S stage glory on 6F
Gain a S stage glory on 5F
Gain a S stage glory on 4F
Gain a S stage glory on 3F
Gain a S stage glory on 2F
Gain a S stage glory on 1F
Gain a S stage glory on Ground Floor
Fix Robot Chef
Collect all 17 letters
Fly and place 20 lanterns
Complete 100% game progress
Take lights from four different lamp posts
Complete task on 6F level without replaying
Complete task on ground level and gain the S stage glory without replaying