Here is the full list of all 33 Undead Horde 2: Necropolis achievements.
Fully restore every building in Necropolis.
Survive 2 minutes in the Necrodome.
Conquer all levels in Citadel.
Slay the mythical Beast of Carmague.
Conquer all levels in Winterlands.
Reclaim the Necropolis Throne.
Kill the Archmage.
Enter Citadel.
Craft an item with three affixes.
Obtain 15 unique rune powers.
Conquer all levels in Desert.
Dig up 10 buried treasures.
Reset your upgrade cards.
Assign 5 nobles to council seats.
Conquer all levels in Darklands.
Include 5 different unit types in your horde.
Upgrade a unit building to level 3.
Enter Desert.
Unlock 10 different unit types.
Gain 100,000 gold.
Complete all merchant's quests.
Destroy a Freezing Monolith.
Find a noble soul jar.
Enter Winterlands.
Reach Level 6.
Stop the elven ritual and kill the ancient fire elemental.
Solve the puzzle in Forgotten Crypt.
Die for the first time.
Restore 10 buildings in Necropolis.
Uncover 5 secrets.
Acquire your first talent.
Claim Scavengers' Bog.
Enter Darklands.