Occasionally when fighting in melee with a weapon you are Expert in, not twoweaponing, and there is no special artifact effect already in play, you get some special benefit of that weapon type. ( Ideas:

• Some of the longer swords allow parrying monsters’ attacks.
• Mace or flail or morning star could stun or confuse targets
• Stiletto gives you automatic counterattacks sometimes.
• Spears can skewer through an enemy and hit another one directly behind it.

Merge Sunsword and Trollsbane like NetHack Fourk does (a single artifact that emits light, instakills gremlins and instapetrifies trolls, with bonuses to undead), except keep it a morning star and name it Sunflash (because a lot of these consolidated effects have nothing to do with trolls). Having it stay a morning star makes it an attractive choice for Priests, and raises the appeal of training morning star.

Artifact morning star, chaotic aligned, with an allusion to Lucifer.