Here is the full list of all 12 Lowglow achievements.
Complete the first chapter.
Complete 5 levels with less lines than the given amount
Complete the second chapter.
Complete the third chapter
Complete the fourth chapter
Complete the fifth chapter
Open your first vault.
Open all of the vaults in Umbralight
Complete 15 levels with less lines than the given amount.
Complete 30 levels with less lines than the given amount. Magnificent!
Complete a level without missing a single drop.
Destroy 50 lines.