The Darkforge Raid Edit
There are a good deal of nice things inside Darkforge, primarily pools, a 4x7 room filled with melee weapons, and a 4x4 room filled with body armor. Weapon and armor quality varies from regular leather armors and iron weapons to artifacts and dragon scale mail. One can reasonably expect to find at least one suit of higher metal or crystal armor, and at least one eternium weapon. Due to the greater size of the weapon room, it is more likely to contain good weapons.
The relationship between PC character level and weapon/armor quality is unknown. It is believed that while the type of the items is unaffected, low character level lowers chances of "ego" weaponry (i. e. weapons with suffixes and prefixes). This a very minor consideration compared to the help the high quality items will be to players of any level, so there is no reason to wait.
The only problem standing between a low level character and these nice things are steel golems. Well, a lot of them, actually. They can certainly be destroyed with construct slaying ammo or Lightning Ball and good Willpower, but these are not easy to get either.
As of version 1.2.0 pre7, controlled teleportation in Darkforge produces the message "You suddenly feel that some sinister force wrenches control from you!" and the PC will teleport randomly. This means that raiding Darkforge is considerably more challenging, as raiding the treasure rooms requires luck with random teleports to arrive at the correct location, and there are similar difficulties with escape. In practice, it may be somewhat infeasible for PCs who cannot kill at least a golem or two to attempt a Darkforge raid in more recent versions.
The usual strategy to bypass the golems is by controlled teleportation (some speedrun attempts used uncontrolled teleportation but this is not recommended).
First you need to get through nondescript dungeon, which is a semi-dangerous place easily featuring troll berserkers and chaos knights. You need either outrun the steel golem guarding the stairs or lure out him and teleport to the stairs, then descend. As soon as you descend a few steel golems in corridor will probably notice PC and wake up. They do not cause danger if the PC teleports immediately - from the stairs, the player can teleport to the armor room by moving between 22 and 26 squares to the left of the starting stairs. The weapon room is between 10 and 13 squares down and between 45 and 51 squares to the left of the starting stairs. If the player is low on teleportation charges, it is possible to create a teleportation trap in either room. In extreme cases, a teleport trap may be created 1 square east of the stairs the player arrived through.
There is an additional steel golem behind each treasure room door so locking doors, if possible, is recommended. The armor room uses a round key, the weapon room a triangular key.
Escaping with the loot is considerably more difficult than getting it. The awakened steel golems near the start of the level tend to congregrate near the stairs and block access.
Hopefully your character can survive one or two hits by steel golems on the way out, but the safest way is probably using multiple torches. Each torch increases the line of sight, so two or three of them should ensure you can see the entire tunnel guarded by golems leading down from the stairs. (Put one torch in tool slot, and dual wield two others). Torches also cancel stealth checks so if you teleport to the lower part of that tunnel with three torches on all golems should start chasing you.
If character does not have enough speed, simply move a few steps away and teleport to some safe place. Wait a bit more as the golems go towards the last known position of the character, freeing the up stairs. Of course, all this luring becames easier and safer with a wand of monster detection.
If the player does not have torches available, keep in mind that two-handed swords of parrying (which weigh 100 stones, same as regular two-handed swords) or halberds of defense (which weigh 80 stones, same as mithril halberds) are common in the weapon room. They both add a high flat DV bonus (16 and 18 respectively) when worn, so for characters that did not bring a well-trained high quality shield, these will come in very, very handy in defending from the steel golems.