Here is the full list of all 21 Warlocks vs Shadows achievements.
Play 10 duels
Play every Warlock
Finish without deaths
Open all chests
Do not skip credits
Kill boss of the Shadow World
Kill bosses of the Frozen Lake
Deal 1 milion damage
Deal 500k damage
Kill boss of the Swampland
Kill boss of the Industrial Wasteland
Cast 5k spells
Kill boss of the Greenlands
Deal 100k damage
Deal 50k damage
Cast 1k spells
Deal 10k damage
Finish the tutorial
Cast 10k spells
Cast 20k spells
Cast 50k spells