From IvanWiki

There are usually two Chest Rooms found randomly in the Gloomy Caves. These are large square shaped rooms with two layers. The outer layer is easily accessible, but the inner layer has walls made of meteoric steel and contains a large treasure chest, containing 1 or 2 special items.

Hmm... how do I get in?

Accessing the Room

There are several different ways you can access the inner room.

• Scrolls - Use a scroll of detect material and detect Mithril. This will reveal the large chest inside the room. Then use a scroll (or wand) of teleportation, and with TeleControl, land on top of the chest. Pick up the chest, teleport yourself back out, and drop it. You must detect the chest first, otherwise you will not be able to land on top of it.

• Tunneling - It is very difficult, but not impossible to tunnel through the meteoric steel walls. Use a Mithril or stronger pick axe.

• Acid - If you don't have a strong enough pick axe, use acid. Sulphuric acid is very useful for this. Just throw the bottle at the wall and within a few seconds it will dissolve. Make sure to have strong acid protection though, or it will melt your feet off too! Another option is to vomit on the wall. This will not dissolve the wall, but if you give it some time, it will cause the wall to rust, which makes it easier to dig through.

• Wand of Door Creation - The wand can create a row of doors in the wall, which you can then open - if you have the key of appropriate shape!

Opening the Chest

Once you get access to the chest, it's now a matter of opening it.

• Lock - These chests require special keys that are very hard to get a hold of. If you somehow have the key, use it!

• Kicking - It's much easier to kick the chest. Make sure it is set against a wall. If it's inside the inner room still, that will be fine. If you use the scrolls method to get it, make sure you drop it next to a wall. Then kick it into the wall until the lock breaks. You will need very strong legs and tough boots for this. Note that this may shatter fragile items inside, which is all the worse since it usually contains extremely valuable items.

• Change Material - You can always change the material into something softer. You will still need to kick it if you don't have the key, but it won't require as much leg strength. An easy way to do this is to get Loraticus angry at you and wield the chest as a weapon. Pray to Loraticus and he will most likely change it into banana flesh. This is much more useful than wasting a scroll of change material.

• Wand of Polymorph - Polymorphing the chest will work on the chest itself, revealing its content without altering it.

• Wand of Striking - One zap is usually enough to break the lock.