Nigthmare has slightly increased chance of rare spanws

game/modules/tome/class/interface/Combat.lua

@@ -2387,7 +2387,7 @@ function _M:getFreeHands()
 end
 
 --- Check if the actor dual wields melee weapons (use Archery:hasDualArcheryWeapon for ranged)
-function _M:hasDualWeapon(type, quickset)
+function _M:hasDualWeapon(type, offtype, quickset)
 	if self:attr("disarmed") then
 		return nil, "disarmed"
 	end
@@ -2398,17 +2398,18 @@ function _M:hasDualWeapon(type, quickset)
 	if not (weapon and weapon.combat and not weapon.archery) or not (offweapon and offweapon.combat and not offweapon.archery) then
 		return nil
 	end
+	offtype = offtype or type
 	if type and weapon.combat.talented ~= type then return nil end
-	if type and offweapon.combat.talented ~= type then return nil end
+	if offtype and offweapon.combat.talented ~= offtype then return nil end
 	return weapon, offweapon
 end
 
 --- Check if the actor dual wields melee weapons in the quick slot
-function _M:hasDualWeaponQS(type)
+function _M:hasDualWeaponQS(type, offtype)
 	if self:attr("disarmed") then
 		return nil, "disarmed"
 	end
-	return self:hasDualWeapon(type, true)
+	return self:hasDualWeapon(type, offtype, true)
 end
 
 --- Check if the actor uses psiblades

game/modules/tome/data/birth/descriptors.lua

@@ -191,6 +191,7 @@ newBirthDescriptor{
 		"Unfair game setting",
 		"All zone levels increased by 50%",
 		"All creature talent levels increased by 30%",
+		"Rare creatures are slightly more frequent",
 		"Stairs can not be used for 5 turns after a kill.",
 		"Player can earn Nightmare version of achievements if also playing in Roguelike or Adventure permadeath mode.",
 	},
@@ -204,6 +205,9 @@ newBirthDescriptor{
 		__game_difficulty = 3,
 		money = 100,
 	},
+	game_state = {
+		default_random_rare_chance = 15,
+	},
 }
 newBirthDescriptor{
 	type = "difficulty",

game/modules/tome/data/talents/chronomancy/chronomancer.lua

@@ -239,7 +239,7 @@ doWardenWeaponSwap = function(self, t, type, silent)
 	
 	if type == "blade" then
 		mainhand, offhand = self:hasDualWeapon()
-		if not mainhand and self:hasDualWeapon(nil, true) then  -- weird but this is lets ogers offhanding daggers still swap
+		if not mainhand and self:hasDualWeapon(nil, nil, true) then  -- weird but this is lets ogers offhanding daggers still swap
 		
 			swap = true
 		end