Find a plank
On the right side of the map, you'll run into an NPC that mentions wooden planks. If you look to the east of him, you'll notice a wooden plank. Head south, where you find a bronze key, and you'll notice a wall that every few seconds has red eyes peek out of it. This is a new type of secret, what I call a passable wall, you can literally wall through the wall and follow the path to the Wooden Plank, collect all twelve for the true ending.

Defeat the Maggot Queen on any difficulty
After you progress passed Floor 3 in Castle Hammerwatch, you'll have to beat your first boss. This boss is the Maggot Queen.

Defeat the Fallen Knight on any difficulty
After you progress passed Floor 6 in Castle Hammerwatch, you'll have to beat the second boss. This boss is the Fallen Knight.

Defeat the Arch-Lich on any difficulty
After you progress passed Floor 9 in Castle Hammerwatch, you'll have to beat the third boss. This boss is the Arch-Lich.

Defeat Worldfire the Red Dragon on any difficulty
After you progress passed Floor 12 in Castle Hammerwatch, you'll have to beat the last boss. This boss is the Worldfire the Red Dragon.

Find a bonus level in Castle Hammerwatch
Progress through Level 3 until you see the Defense Vendor in between two blue spike traps. Once you are there, you should begin to look around for five button switches. From the Defense Vendor, head southeast to find a button located on a pillar. From there, head straight east to a small room. After that button, head to the north and it is on the northeast corner. Next button is located in the northwest corner. After that, head southwest to a floor button to turn off the spikes and the last button is to the southwest with a plant enemy. Activating all five switches opens a room to the east where you have to solve a DDO Puzzle. Once you have solved the puzzle you may proceed into the portal to the Gauntlet Bonus Level.

Complete all the bonus levels in Castle Hammerwatch
There are four Gauntlet Bonus Levels to complete in Castle Hammerwatch in order to unlock this achievement. Details for unlocking each Gauntlet Bonus Level can be found in my Secrets guide.

Escaped the destruction of Castle Hammerwatch
Collecting all 12 Wooden Planks will allow you to achieve the true ending of Castle Hammerwatch.
There is one Wooden Plank for each of the twelve floors. Details for locating each of the twelve Wooden Planks can be found in my Secrets guide. https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3024276348

Escaped the destruction of Castle Hammerwatch on Serious difficulty
Collect all 12 Wooden Planks and beat Worldfire the Red Dragon on the Serious difficulty.

Upgrade a shop to maximum in the Sun Temple campaign
While exploring the Sun Temple, you'll come across Keltonite Ore. Use this ore to upgrade the shops in the City of Stone, upgrade one to Level 5 and you'll unlock this achievement.

Return the frying pan to its owner
While exploring the Desert Caves, you should come across a Frying Pan. The pan can be in a random location. Return it to the vendor with the maze symbol above their head in the City of Stone to unlock the Powerup Vendor and achievement.

Return the pickaxe to the miner to clear the rocks
While exploring the Sun Temple Middle Floor, you should come across a Pickaxe. Return it to Lyron the Pickaxe Man in the City of Stone to unlock this achievement.

Return the level to its rightful place to drain the waters
Before you fight Krilith the Frost Sorceror, you must first find the lever and drain the water in the Desert Caves. You will find the lever in Sun Temple Lower Floor (Image 1 and 2) and use the pump in Desert Cave Nesting Grounds (Image 3 and 4).

Enter and exit the Pyramid of Fear located southeast of the City of Stone.
In order to unlock the Pyramid of Fear you must first activate the six small pyramids located in the Sun Temple. Once activated head to the southeast of City of Stone to enter the bonus level.
Details for locating each of the six small pyramids can be found in my Secrets guide. https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3024276348

Defeat the Desert Sharks on any difficulty
After you progress passed Desert Cave Spider Hollows, you'll find yourself in The Arena. Proceed to the teleporter, then you'll have to beat your first boss. This boss is the Desert Sharks.

Defeat Krilith the Frost Sorcerer on any difficulty
After you progress passed cleared the first floor in the Sun Temple, you'll find a pump lever and drain the waters from the Caves. Then you'll have to beat the second boss in the Abandoned Storage Room, staircase located in Desert Cave Spider Hollows. This boss is the Krilith the Frost Sorceror.

Defeat Sha'rand the Sun Guardian on any difficulty
After you activate all six solar nodes in Sun Temple, you'll be able to take the boss portal located in the northern part of City of Stone. You will have to beat the final boss. This boss is the Sha'rand the Sun Guardian.

Survived the Sun Temple on Serious difficulty
Defeat Sha'rand the Sun Guardian on Serious difficulty, then return to the City of Stone and talk to Richard Cain to finish the campaign and unlock this achievement.

Rescued the apothecary in the mines.
You will find the Apothecary in the Keltonite Mines.

Restored the fountain
The Bucket can be found in the Infested Prison and used to collect water from one of the many sources in the tower. Bring the water back to the fountain in The Outlook and you'll get this achievement.

Got the ore from the miner
After defeating the Stone Golem, talk to the miner in the northwest corner of The Outlook. He will go to Keltonite Mines Floor 1. Find him there and collect his ore to get this achievement.

Help out a miner with a big rock
On Keltonite Mines Floor 3, you'll find a miner standing near a big rock. Push it off the ledge and you'll begin the quest. The next step is to find the miner and rock on Keltonite Mines Floor 2 and push it off the ledge here. Finally, find the miner with the broken rock on Keltonite Mines Floor 1 and collect your loot.

Find a dangerous but lucrative cave in the Mines
On Keltonite Mines Floor 3, you'll find a staircase marked with a "?". Take the stairs and you'll find a mining game where you collect ore pieces and turn them into ore or gold.

Release some prisoners and find a treasure
In the Infested Prison, you'll have to go around each floor and find an item to free a prisoner on that floor. On Floor 4, you're looking for a Dull Hacksaw on the east side of the map and the prisoner is located in the northeast corner of the map. On Floor 5, you're looking for a Rusty Crowbar and the prisoner is located on the southwest corner of the map. On Floor 6, you're looking for a Bent Hairpin and the prisoner is located in the center of the map. Once you find the items on each floor, you can unlock the prisoner on that floor. After talking to each of the prisoners they will return to The Outlook. Release all three and they'll tell you about a treasure on Infested Prison Tower Floor 6. Once you find that treasure an achievement will unlock. NOTE: Upon further testing, you don't need to release the prisoners to find the treasure, but I am unsure if you can get the achievement this way.

Find the real testing place of the duke
While exploring the Haunted Barracks you'll have to find breakable walls with a dead duke inside each, four total. Once inside each of the four rooms you'll need to search the bookshelves, bed and/or table to find a teleport key. After you have found all four, return to the teleport that you needed the keys for on Haunted Barracks Tower Floor 7. This will get you the achievement as well as the Magical Mirror to use glasswalk throughout the entire tower.

Solve the curious book's code
After finding the Duke's treasure, you'll find somebody in town that mentions using ROT13 to translate the pages found in the Demonic Library that appear to be gibberish. One mentions a secret near the map. There is a map for a maze hidden in a wall you can pass through. Southeast of that map is a wall you can pass through to get some gold and this achievement.

Solve a dispute over a room
After defeating the Vampire Count, return to the teleport on the inside of Chamber of Sacrament Tower Floor 14. Once you are there, directly to your west is an NPC you can talk to, return to The Outlook after speaking to them and head to the northwest corner. In a room in the back of the building will be an NPC who wants you to hang a sword beside the first NPC in the Chamber of Sacrament. After this you'll go back and forth talking between these two NPCs until the one in the Chamber of Secrets returns to The Outlook. Once you speak to them at The Outlook, you'll get a Legendary Inventory Item and the achievement.

Overcome four challenges and find a powerful book
While exploring the entire tower, you'll come across four separate red portals hidden behind secret walls. You'll have to destroy the cube in the center of the room to get the loot. The item you need is Chaos Orb. After collecting all four Chaos Orbs, progress to Tower Battlements Tower Floor 16 and just before the final boss gate the place for the Chaos Orbs is to the west.

Avenge a fallen magician
On the east side of Tower Battlements Tower Floor 16, you'll find a glasswalk that leads to arrow traps and a gargoyle that upon defeating an NPC will spawn and ask you to complete a quest. Proceed into the teleport that spawns and beat the boss for the quest. Once you have returned and talked to the NPC that gave you the quest you will get the achievement.

Fixed all the elevators in the tower
There is a toolbox located in each zone that will fix the elevator for that zone. Find them all to get this achievement and to successfully escape the destruction of Shaftlocke Tower. Details for locating each of the toolboxes and lifts can be found in my Secrets guide. https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3024276348

Upgrade all the shops to maximum in the Shaftlocke Tower campaign
You can upgrade the vendors by collecting ore in the tower and spending it at the mayor in the center of The Outlook.

Defeat the Stone Golem on any difficulty
After you progress passed Keltonite Mines Tower Floor 3 in Shaftlocke Tower, you'll have to beat your first boss. This boss is the Stone Golem.

Defeat the Warden on any difficulty
After you progress passed Infested Prison Tower Floor 6 in Shaftlocke Tower, you'll have to beat the second boss. This boss is the Warden.

Defeat the Wraith Councilors on any difficulty
After you progress passed Haunted Barracks Tower Floor 9 in Shaftlocke Tower, you'll have to beat the third boss. This boss is the Wraith Councilors.

Defeat the Watcher on any difficulty
After you progress passed Demonic Library Tower Floor 12 in Shaftlocke Tower, you'll have to beat the fourth boss. This boss is the Watcher.

Defeat the Vampire Count on any difficulty
After you progress passed Chamber of Sacrament Tower Floor 14 in Shaftlocke Tower, you'll have to beat the fifth boss. This boss is the Vampire Count.

Defeat Thundersnow the Blue Dragon on any difficulty
After you progress passed Tower Battlements Tower Floor ** in Shaftlocke Tower, you'll have to beat the final boss. This boss is the Thundersnow the Blue Dragon.

Escaped the destruction of Shaftlocke Tower
Collect the toolboxes in each zone and repair the elevators in each zone and you will be able to use the lifts to escape Shaftlocke Tower after defeating Thundersnow the Blue Dragon.

Escaped the destruction of Shaftlocke Tower on Serious difficulty
Collect the toolboxes in each zone and repair the elevators in each zone and you will be able to use the lifts to escape Shaftlocke Tower after defeating Thundersnow the Blue Dragon. Do it on Serious difficulty to get this achievement.

Acquire 100,000 coins
Pretty straight forward, there is gold in the game and when you collect a total of 100,000 coins across all of your playthroughs you will get this achievement.

Defeat 25,000 enemies
Pretty straight forward, there are enemies in the game and when you kill a total of 25,000 of them across all of your playthroughs you will get this achievement.

Reach a count of at least 500 in a single combo
This one can be a little tricky, but I recommend focusing on a class that can clear rooms quickly.
My preference for this one was a Thief, but realistically any class can achieve this. I recommend stacking Combo Timer and Combo Nova.