Here is the full list of all 41 Morrow achievements.
Kill 100 crawlers
Kill 100 ogre heads
Kill 100 fortuners
Kill 100 jesters
Collect the undead book of Zombiet
Collect the eternal monolith of Ari the unbreaking
Kill 100 knights
Complete the farmland stage
Kill 100 onions
Collect the diamond tusk of Cinghiale
Slay Cinghiale and Wiis
Kill 100 MutAnts
Get 1000 kills with the bard
Get 1000 kills with the berzerker
Collect the eye of Rutskin
Kill 100 goblins
Get 1000 kills with the archer
Collect the cape of Berlad
Get 1000 kills with the wizard
Kill 100 scarecrows
Kill 100 peasants
Open the game for the first time.
Kill 100 crows
Get hit by 20 rat swarms
Kill 100 skeletons
Kill 100 ogres
Kill 100 ghosts
Kill 100 plague doctors
Kill 100 big rats
Kill 100 slimes
Slay Admiral Nedos
Slay Kevin Tarantino
Complete the Castle Walls Stage
Complete Morrow!
Collect the flame gem of general Nedos
Collect the infinity elixir of Arsilan
Collect the soul mirror of the underworld
Maxed out all perks
Unlocking the cheats page
Collect Kevin's Railbow
Kill 100 null enemies