|A blade forged in Hell by the sacrifice of countless tortured souls. It inflicts the rage and suffering of those souls upon its wielder.|
+8 demon blade
Similar to but somewhat weaker than the zealot's sword, Bloodbane is a very nice weapon if you can overcome its berserkitis. Being undead or worshiping Ashenzari will give you a bit more leeway for using this weapon, and the fact that it doesn't curse itself constantly means you can use it whenever a situation arises in which berserking would actually be useful. Just don't wield it all the time and you'll be fine.
Prior to 0.18, the forced berserk happened on 9% of attacks.
Prior to 0.15, stealth penalty was -20.