Eye of the Beholder 2 Walkthrough - The Silver Tower, Level 4
Four Dark Moon Keys
After two flights of stairs from Level 3 you get to a teleporter. In this first part of Level 4, you will be teleported randomly to one of six areas. Four of the areas each have a dark moon key. The other two areas are the starting area (leading back down to Level 3) and the destination area with four dark moon keyholes. Once you have collected all four keys, use them in the destination area to open the door that will allow you to proceed. It is a good idea to make use of a good map, such as this one, as it's very easy to get lost in this level.
This level is inhabited by beholders and will-o-wisps. Aside from being immune to magic, the beholders have a tendency of throwing death spells at you, so you need to dodge them continuously. The problem is that most of the time there isn't space to dodge them, so you have to run away and ambush them from behind a corner. At the beginning of the level, just beyond the door, you will encounter the first three beholders. Since there is no space, Haste really helps to cut them down before they corner you. In the first right turning, you will find a secret button that reveals three potions of healing. There is also an illusionary wall that leads directly to the illusionary maze.
If you keep trekking straight ahead, you get to a wide corridor to the west. Always going straight (south), you get to a shelter area (as described by the plaque). Further on is an area with wisps that try to lure you into a deadly fireball trap. Ignore them and move on.
Round the corner is another shelter. Beside the plaque is a secret button that leads to the illusionary maze.
Towards the centre of the level, through one of two access points described earlier, you will reach a maze of illusionary walls. It's easy to get lost since you will only be able to see walls all around you, so use the map you found in Level 3 to get your bearings. Your objective is to reach the southern room.
As you approach, you will find a beholder stuck in a hole in the ceiling. If you help him, he will attack you. If you try to kill him, he will escape and then attack you once you ascend, so it doesn't really make a difference what you choose.
Click on the button that looks like a tornado to be blown upwards through the pit. If you attacked the stuck beholder, he will now fight you. Since there is some space to move around, killing him is not a big deal. In this small sub-area of Level 4 you are about to find what is probably the biggest stash of magical items in the game.
Another beholder awaits along the corridor, and you will find 2 femurs and -2 cursed bracers of protection at an intersection. For some reasons, the cursed bracers do not stick to your hands like all other cursed items do, so Remove Curse is not necessary.
At the end of the hall you will find a +2 halberd, a +3 shield, a +2 crystal hammer, 2 regular daggers, a staff, leather boots, and a potion of healing. The crystal hammer is a unique and essential item that you need to access the Azure Tower.
Behind the door in this area are three beholders. At your immediate left int this room is a femur, rotten rations, and iron rations. At the end on the right is a regular mace and a mage scroll of fireball.
Going through the second door, at your immediate right, is dragon skin armour +4 (which is crap) and a short sword +2. At the far end you will be surprised by another beholder who is sitting on a femur, a skull, and a wand of dispel magic.
The Mark of Darkmoon
Go back down the way you came. Taking the north exit from the illusionary maze, head southwest. Khelben appears, and you manage to tell him about Dran before the communication is broken.
Moving on, a plaque warns you about the Test of Vision. This is probably the most confusing area in the game - there are invisible teleporters that will throw you around without warning, and pressure plates that alter the geography. Using a good map, take the shortest route to the northeastern part of the level, passing through the spinner.
On a southern wall (marked as location 42 on the map) there is a secret button acting as a switch (i.e. you can turn it off and on) but I have no idea what it does. Shortly after, at location 38, you will find a ring of sustenance, a regular chainmail, and rations.
On the eastern wall is another secret button that reveals the way onwards. At the end of the passage you reach a chamber where the overseer of the Test of the Cloth teleports two beholders in. You can either kill them or run to the pedestal.
Either way, you need to get your hand on that pedestal. This will give you the Mark of Darkmoon (visible on each character's right hand if you remove their weapon) and teleport you back to the Temple entrance. You now have all you need to proceed to the Azure Tower.