Morrowind:Eltonbrand

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Artifact: Eltonbrand (katana_bluebrand_unique)
Type	Long Blade One Hand
Damage
Chop	10−60	Slash	5−55
Thrust	5−25	Ratio	90(110 w/ spell)
Statistics
Health	4,500
Speed	1.5	Reach	1.0
Weight	40	Value	150,000
Enchantment
Cast When Strikes     Fire Damage 10−30 pts on Touch     Fortify Attack 30 pts for 30 secs on Self     Restore Fatigue 10 pts on Self
Charge/Cost = Uses		500/5 = 100

Eltonbrand is easily the most obscure item to get within the game. Unless you know how, or are very, very lucky, you will not find it yourself. First you must obtain the Goldbrand sword, which itself is one of the most difficult to acquire items. Next you need to become a vampire and perform the Shashev's Key quest for Sirilonwe in the Vivec Mages Guild. It is at this point that it appears you can 'mess' this quest up if you do it improperly, and thus spoiling your chances of obtaining Eltonbrand. The best course of action is to obtain the quest from Sirilonwe, kill Shashev and take his key back to Vivec. If you kill Shashev before speaking to Sirilonwe, you are likely to ruin everything. Once you have Goldbrand and complete the quest, you'll need to be carrying exactly 11171 gold for the magical transformation of Goldbrand into Eltonbrand (you don't lose the gold).
This weapon is an Easter egg.