Okay. The King of the Undead's Cloak is 100% good. But it's only for Necropolis, so I'm not considering it.
Cursed Armor.
For 50 turns, all opponents are affected by the spells: slow, curse, weakness, and misfortune.
Sniper Bow.
Remote archers can shoot as long as there is an enemy creature nearby. No problem with long distances.
Which is better? It depends on the player. If you have a lot of archers, take the bow, and if you like to mess with your enemies, take the armor!
P.S. I would still take the armor!
instead of, say, the Haven faction...