http://www.kiya1.de/images/Silverarmour.htmlEaster egg => you need a few requirements in order to get teleported to it - please, read the description in the link. As it is a spoiler link, the answer in short:
You need access to the teleporting area by having 4 treasure maps. As soon as you're in that area (cave in the Dark Forest), you need:
Silver armour
2002 gp and not one coin more or less
5 bottles of Rimmer ale (Glenborus, dwarven village)
4 ropes from the teleporting area - and only those!
1 pyramid stone safely outside and one in your inventory, so you can return to the main game area
Patience, you will find out why you can't kill Janus at the game stage you're in. Janus (or what he turned into) is part of the main plot. If you were able to kill him now, you couldn't continue with the game.
Though, I'm asking myself, how you will be able to kill, if you're missing a CD <img src="/ubbthreads/images/graemlins/think.gif" alt="" /> (one of your former posts)
Kiya