Here is the full list of all 19 Bloom: Roots of Renewal achievements.
Complete The Ruins only using the single shot
Kill 400 Enemies
Complete The Ruins
Kill 20 Poisonous Plants
Kill 50 enemies with the Machine Gun
Kill 25 Ents
Kill 100 Enemies
Complete The Ruins in less than 6 minutes
Kill 1,000 Enemies
Kill 20 Spiders
Pick Up A Weapon
Complete The Village
Complete The Archives
Obtain a score of 22500 on The Ruins
Kill every enemy in a given level
Collect Every Book
Kill 3 enemies with one Triple Shot
Kill an enemy at least 50m away with the sniper
Kill a flying enemy while in the air