Black Knight's Fortress

Walkthrough
First of all, to save time, get the items. Grab a cabbage from the monastery near the black knight's fortress (cabbage taken from Draynor Manor will not work, you will find out why during the quest), buy an iron chainmail from Wayne's Chains in Falador, and buy a medium bronze helmet from Peksa in Barbarian Village. If your smithing level is high enough (3 for the Bronze Medium Helmet, 26 for the Iron Chainbody), you can just smith the chain and the helmet. If not, you'll have to buy them.

Talk to Sir Amik Varze. He will tell you that he needs a spy. He wants you to spy on the black knights for him at their fortress located northeast of Falador on Ice Mountain. He wants you to find out what their new weapon is and destroy it.

Make your way to the fortress. It is north east of the Dwarven Mines and the Oracle. Run through the Black Knights, as they will attack you because they are naturally aggressive. Enter the door to the south surrounded by guards. Make sure you are wearing the iron chain and the bronze medium helmet. If you are wearing the chain and the helmet, you can enter. If you are not, the guards will not let you enter.

Once inside, the wall right in front of you can be pushed. Push it to enter a small room. Climb up the ladder in this small room and then up the ladder immediately to the right of it. Climb down the ladder just south, go through a door to the east and then up another ladder. Climb down the ladder beside the one you just came up and you will end up in a room with a Chaos altar. Open the door and run to avoid the knights. Climb down the ladder to the southwest and you will find yourself in a small room. In this small room, there should be a grill. Click on it to listen. You will hear a conversation between a witch and a goblin. Dropping the cabbage creates a strange reaction.  F ollow the ladders back to the room with the false wall and try to open the door to the east where many black knights are walking around a table. You will be stopped from opening the door, since a guard will talk to you. He will say that there is an important meeting going on and they'll kill anyone who gets in. Say you don't care and that you're going in anyway. Run from the knights and climb up the ladder on the north wall of the room. Walk east and south and look for a wall you can push. Push the wall to see a hole. RIGHT CLICK your cabbage so that you do not eat it, and use it with the hole that should be in the room. You will hear the witch groan, meaning you destroyed the weapon.

Now go back to Sir Amik Varze and tell him you sabotaged the weapon. When he is done talking, you will have finished the quest.

Reward



 * 3 Quest Points
 * 2500 coins

Trivia

 * The quest point requirement was added to discourage players from creating new accounts to do the quest and transfer the 2,500 coins to their main characters. When the quest was first released, 2,500 coins was considered very valuable at the time.
 * At first, the quest gave around 250 Thieving experience as a reward. Thieving was in the skill menu at the time, but had not been programmed yet. The skill was later removed and added back in 2002, but the quest no longer gives Thieving experience.