Here is the full list of all 49 Death Must Die achievements.
A d20 of 400
Not a scratch
33 Sync-Ups
The magic of friendship
50 Shields for my wall
Stop the evil old man
25 With a single blow
Instant bash
On the hunt for a bat
I need 40 good men
A cat dies 9 times
A stake for a vampire
100000 Wounds Inflicted
Time travelling twice for victory
Get 8 visual effects
What we do in the 10th shadow
4 Times jumper
300 Steps
Number go up to 30
I wield the 5 elements
999 Bandages
I don't need no handouts
Do not take the purple bait
5 Lamps to turn off
Defeat the Baron
50 Summoning orders
4000 Pounds of jelly
20 Seconds for two bats
6000 Bones to pick
A total of 2000 natural 20 damage
A red and a blue bat
500 bones under the sword
Win an attempt as Avoron using the Light Rays blessing from Lady Justice
Travel to 40 different locations in an attempt as Avoron.
Win an attempt as Merris using the Telekinesis talent
Win an attempt as Merris using the Charged Field talent
Win an attempt as Nixi using the Endless Night talent
Win an attempt as Nixi using the Mind Reaper talent
Win an attempt as Front using the Rampage talent
Defeat The Djinn as Front
Win an attempt as Skadi and her wolves
Win an attempt as Skadi with Darkness
Level up to 40 as Lorien
Kill 1000 Skeletons as Lorien
Lose an attempt as Lorien
Defeat The Insect Queen as Lorien
Traverse 50000 distance as Lorien
Win an attempt as Lorien using the Bask in Greatness talent
Win an attempt as Lorien using the Whistling Arrow talent