ensured defeat if Erlornas dies

see

http://forums.wesnoth.org/viewtopic.php?f=4&t=33889&p=489562#p489562

data/campaigns/An_Orcish_Incursion/scenarios/05_Linaera_the_Quick.cfg

@@ -297,6 +297,7 @@ Use Elven Scouts and Linaera’s power of teleportation to mount hit-and-run att
             result=defeat
         [/endlevel]
     [/event]
+    {campaigns/An_Orcish_Incursion/utils/deaths.cfg}
 
     [event]
         name=enemies defeated

data/campaigns/An_Orcish_Incursion/scenarios/06_A_Detour_through_the_Swamp.cfg

@@ -142,6 +142,7 @@ Undead are resistant to physical attack. Use mages to attack the undead, and elv
             result="defeat"
         [/endlevel]
     [/event]
+    {campaigns/An_Orcish_Incursion/utils/deaths.cfg}
     [event]
         name="enemies defeated"
         [role]

data/campaigns/An_Orcish_Incursion/utils/deaths.cfg

@@ -0,0 +1,11 @@
+#textdomain wesnoth-aoi
+
+[event]
+    name=die
+    [filter]
+        id=Erlornas
+    [/filter]
+    [endlevel]
+        result=defeat
+    [/endlevel]
+[/event]