Refactor Game Modes (#5819)

Content.Server/Objectives/Conditions/KillRandomPersonCondition.cs

@@ -28,6 +28,10 @@ namespace Content.Server.Objectives.Conditions
                        mobState.IsAlive() &&
                        mc.Mind != mind;
             }).Select(mc => mc.Mind).ToList();
+
+            if (allHumans.Count == 0)
+                return new DieCondition(); // I guess I'll die
+
             return new KillRandomPersonCondition {Target = IoCManager.Resolve<IRobustRandom>().Pick(allHumans)};
         }
     }