This is mRO link for Lv4 Weapon Type S.
http://ero.gameflier.com.my/homepage/questweapons.html

STEPS:
1. Talk to P.Shadow (aldebaran 178 239) at Aldebaran. And he’ll tell you he used to be a great forger but now mourning about his lost sons and ask you to leave.

2. Go to Niflheim and talk to 1 of his 4 sons (depend which weapon you want to make). He don’t know what he’s trying to express. Probably coz of less fatherly love. Choose “Show concern.”
3. Go back aldebaran and talk to P.Shadow. He’ll tell you about his son and there’ll a hint in his conversatoin.
4. Go back and talk to his son. A window will pop up.
Key in
Haye Ying: [If you take out the money before gambling.]
Potter Paster: [the successful person always work hard!]
He’ll ask you to collect Hammer of Blacksmith x 2, Emperium Anvil x 1, Illusion Flower x 1, Gold x 20.
5. Once you collect all the items he require talk to him again. He’ll take you item and say yoo still need special ores but he can’t remember.
6. Go to Aldebaran and talk to P.Shadow. He’ll random tell you 1 out of 2 weapon group ingredients needed to make the Lv4 Weapon Type S. (which mean you have 50% to get 1 of the 2 weapons group.)
7. Once you make up your mind, bring 1 of the ingredients to that NPC in Niflheim (depend which weapon you want to make). You’ll need to play “Rock, Scissors, Paper” with him and win 2 out 3 tries.
8. If you fail, you’ll lost 30 special ores of 1 type and you’ll need to collect and try again. If you success then talk to him again and he’ll give you 1 out of 2 weapons (which mean another 50% chance u get 1 of the 2 weapon.. so it’s like 25% chance u’ll get for the weapon you intend to get. )
*Actually you can skip the 1st step and proceed the 2nd step.