Eye of the Beholder 2 Walkthrough - The Catacombs beneath Darkmoon
The main entrance of the catacombs is a large room. To your left you will find a locked door, while to the right is another door that you can open with a button. Taking the latter route, you get to a door that is opened when you step on the pressure plate before it. Guards will attack you as you enter, and one drops a grey key.
From here, there are two possible routes. There is a passage and a door with a lever. For now, follow the passage.
At the end of the passage is another door with another pressure plate in front of it. Unlike the first door, this one does not remain open when you step off the pressure plate. Put something on the pressure plate to keep the door open.
As you enter the new room, to your right you will find a grey key in a niche. Use it to open the locked door, where you will find Insal the Thief.
Insal is the first NPC you meet. Unfortunately, he is of very little use...
...since he leaves the party and steals some of your items as soon as you rest with him in the party. Naturally, not resting for the rest of the game is not an option.
You could certainly benefit from Insal's added inventory, but you can't let him escape with your items. Fortunately, you can keep him on your party by having him killed. There is a guard at the other end of the room. Give him your back, and he will kill Insal. His attacks are pretty weak, so you may want to speed things up by casting Fireball and walking into it.
After you kill that guard (who drops lock picks when you kill him), check out the barrels behind him. They contain rations and 3 bags of magic dust, which you will need later if one of your characters gets petrified.
The Spider sub-level
The note that Insal leaves if you let him rob your party hints at a secret door in the room with the barrels. Look for a small button on the same wall as Insal's door lock is. This will reveal a staircase down.
The large cobwebs that bar your way are an immediate sign that spiders inhabit this area. Make sure you have Neutralize Poison in your cleric's current repertoire before cutting up the cobwebs.
There isn't much to this level. After killing two or three spiders you will find a few items in a corner. These include bones that crumble to dust as you touch them, a cleric scroll of neutralize poison, a parchment, a mage scroll of magic missile, and a copper key. The parchment shows a secret door in another area that you will be visiting shortly.
The Food Store
Go back to the door with the lever and open it. After killing the guard, you will find that this is a food store. 3 iron rations are here for the taking.
The Pit Trap
Backtrack to the catacomb entrance and use the grey key you got from the guards earlier to open the door. Kill the guards (my paladin advanced to Level 7 during this fight). In the corridor that follows, you find a pit. A party member remarks about the lever closing the pit, but that a trap follows. Pull the lever to close the pit. As you step on the pressure plate after the pit, it reopens behind you. The door before you also opens, and guards come to attack you.
If you step back, you will fall in the pit. If this happens, throw an object through the prison cell door to open it.
Kill the guards and collect their loot (2 grey keys and 2 scale mails). As the corridor bends, look for a small button on the wall (given away by the map you found earlier) to reveal a path down to the prison area. This is the same place where you end up if you fall through the pit.
Note that as soon as you take a staircase down from this level, you will have to answer a copy protection question. If you skip this part, you will be asked anyway at the second staircase after the barracks.
A button opens the door to the cell where you fall from the pit. Another cell door is locked, but you can pick the fancy-looking lock and the door will open behind you. Here, you find a mage scroll of lightning bolt, and a skull. Lightning bolt is an awesome spell that surges through your enemies and causes lots of damage, so scribe it to your mage's spellbook.
Go back up and continue following the passage. Use a grey key to unlock the guard station door, and kill them all. My Fighter/Thief got his Thief Level 7 during this fight. The guards drop a long sword, and you will also find a magical dagger by examining the basin.
Further down the corridor, you will find a door on either side. Pick the fancy-looking lock and kill the two guards in there to get another grey key. Use it to open the other door, where you will find a horn called the North Wind, and a parchment hinting at its purpose.
At the end of the corridor are stairs leading down. As soon as you go down the stairs, look for a button in the wall to your right. Pressing this button will make a niche appear on the wall. This niche contains a sling and a cleric scroll of Raise Dead.
At the end of the corridor you will find another downward stairway, leading to the next major level beneath Darkmoon.