diff --git a/gamebase.py b/gamebase.py
index 06cc4bd..c992716 100644
--- a/gamebase.py
+++ b/gamebase.py
@@ -235,10 +235,12 @@ Object can be the name of the object, or its coordinates."""
             if args[0] == 'the':
                 args.pop(0)
             thing, x, y = self.parseCoords(args, usePlayerCoords = False)
-            if thing:
-                print(self.justifyText(str(thing)), file = self.outstream)
-            else:
+            if not self.level.lineOfSight(self.playerx, self.playery, x, y):
+                print("{} cannot see that.".format(self.playerName))
+            elif thing == None:
                 print("There is nothing to see here.\n", file = self.outstream)
+            else:
+                print(self.justifyText(str(thing)), file = self.outstream)
         #_hq.heappush(self.eventQueue, (self.gameTime, _ge.NoOpEvent()))
         
     def use(self, args):
diff --git a/gameevents.py b/gameevents.py
index 9adeef6..fb61598 100644
--- a/gameevents.py
+++ b/gameevents.py
@@ -98,3 +98,8 @@ class DropEvent(GameEvent):
     def __init__(self, item):
         super(DropEvent, self).__init__('drop')
         self.item = item
+
+class BehaveEvent(GameEvent):
+    def __init__(self, actor):
+        super(BehaveEvent, self).__init__('behave')
+        self.actor = actor
diff --git a/gamemap.py b/gamemap.py
index 27be546..6529fdc 100644
--- a/gamemap.py
+++ b/gamemap.py
@@ -3,6 +3,7 @@ import re
 import heapq
 import xml.etree.ElementTree as ET
 import ruamel.yaml
+import math as _mt
 from ruamel.yaml.comments import CommentedMap # for loading classes
 
 class Thing(object):
@@ -121,9 +122,6 @@ class Useable(Thing):
         self.useFunc = useFunc
         self.customValues = customValues
         self.graphic = graphic
-        
-    def use(self):
-        pass
     
     @classmethod
     def to_yaml(cls, representer, node):
@@ -182,12 +180,15 @@ class Useable(Thing):
             parts['description'], useFunc, customValues, playerx, playery, graphic)
 
 class NPC(Thing):
+    yaml_flag = u'!NPC'
+    defaultGraphic = ('clear', '#000000', 'o')
     
-    def __init__(self, name, x: int, y: int, description: str, friendly = True, following = False, graphic = ('clear', '#000000', 'o')):
-        super(NPC, self).__init__('c', name, x, y, description, 6)
+    def __init__(self, name, x: int, y: int, description: str, behavior: str, inventory: list, customValues: dict, playerx = None, playery = None, following = False, graphic = defaultGraphic):
+        super(NPC, self).__init__('c', name, x, y, description, 6, playerx, playery)
+        self.behavior = behavior
         self.following = following
-        self.friendly = friendly
-        self.inventory = []
+        self.inventory = inventory
+        self.customValues = customValues
         self.graphic = graphic
         
     def give(self, item):
@@ -198,6 +199,69 @@ class NPC(Thing):
         
     def dialog(self):
         pass
+        
+    @classmethod
+    def to_yaml(cls, representer, node):
+        # save usual things
+        ret = {'name': node.name, 'location': (node.x, node.y),
+            'description': node.description, 'behavior': node.behavior}
+        # save graphic
+        graphic = {}
+        if node.graphic[0] != NPC.defaultGraphic[0]:
+            graphic['bgc'] = node.graphic[0]
+        if node.graphic[1] != NPC.defaultGraphic[1]:
+            graphic['fgc'] = node.graphic[1]
+        if node.graphic[2] != NPC.defaultGraphic[2]:
+            graphic['shape'] = node.graphic[2]
+        if len(graphic) > 0:
+            ret['graphic'] = graphic
+        # save use functions
+        if node.following:
+            ret['following'] = node.following
+        if len(node.inventory) > 0:
+            ret['inventory'] = node.inventory
+        if len(node.customValues) > 0:
+            ret['customValues'] = node.customValues
+        if node.x != node.playerx or node.y != node.playery:
+            ret['useLocation'] = (node.playerx, node.playery)
+        return representer.represent_mapping(cls.yaml_flag, ret)
+    
+    @classmethod
+    def from_yaml(cls, constructor, node):
+        parts = CommentedMap()
+        constructor.construct_mapping(node, parts, True)
+        # set default values for optional arguments
+        following = False
+        inventory = []
+        customValues = {}
+        playerx, playery = parts['location']
+        bgc = NPC.defaultGraphic[0]
+        fgc = NPC.defaultGraphic[1]
+        shape = NPC.defaultGraphic[2]
+        # load graphic
+        if 'graphic' in parts:
+            if 'bgc' in parts['graphic']:
+                bgc = parts['graphic']['bgc']
+            if 'fgc' in parts['graphic']:
+                fgc = parts['graphic']['fgc']
+            if 'shape' in parts['graphic']:
+                shape = parts['graphic']['shape']
+        graphic = (bgc, fgc, shape)
+        # load use functions
+        if 'following' in parts:
+            useFunc = parts['following']
+        if 'inventory' in parts:
+            inventory = parts['inventory']
+        if 'customValues' in parts:
+            customValues = dict(parts['customValues'])
+            for v in customValues:
+                if isinstance(customValues[v], tuple):
+                    customValues[v] = list(customValues[v])
+        if 'useLocation' in parts:
+            playerx, playery = parts['useLocation']
+        return cls(parts['name'], parts['location'][0], parts['location'][1],
+            parts['description'], parts['behavior'], inventory, customValues,
+            playerx, playery, following, graphic)
 
 class Door(Thing):
     yaml_flag = u'!Door'
@@ -713,19 +777,65 @@ The closeEnough parameter will create a path that lands beside the source if nec
         #    return -1, [] # meaning you can't get there
         
     def lineOfSight(self, x1, y1, x2, y2):
-        pass
+        Dx = x2 - x1
+        Dy = y2 - y1
+        y = y1 + 0.5
+        x = x1 + 0.5
+        lst = []
+        if abs(Dx) >= abs(Dy):
+            if Dx < 0:
+                x = x2 + 0.5
+                y = y2 + 0.5
+            dy = Dy / Dx
+            while(x < max(x2, x1) - 0.5):
+                x += 1
+                lst.append(self.coordsToInt(_mt.floor(x), _mt.floor(y)))
+                if _mt.floor(y) != _mt.floor(y + dy):
+                    lst.append(self.coordsToInt(_mt.floor(x), _mt.floor(y + dy)))
+                y += dy
+        elif abs(Dx) < abs(Dy):
+            if Dy < 0:
+                x = x2 + 0.5
+                y = y2 + 0.5
+            dx = Dx / Dy
+            while(y < max(y2, y1) - 0.5):
+                y += 1
+                lst.append(self.coordsToInt(_mt.floor(x), _mt.floor(y)))
+                if _mt.floor(x) != _mt.floor(x + dx):
+                    lst.append(self.coordsToInt(_mt.floor(x + dx), _mt.floor(y)))
+                x += dx
+        
+        # Here is where we actually check:
+        for space in lst:
+            if not self.isPassable(space):
+                return False
+        return True
+            
+    def isPassable(self, x, y = -1):
+        pos = x
+        if y == -1:
+            x, y = self.intToCoords(x)
+        else:
+            pos = self.coordsToInt(x, y)
+        if self.mapMatrix[y][x][0] == 'w':
+            return False
+        thingsInSpace = self.getThingsAtPos(pos)
+        for thing in thingsInSpace:
+            if not thing.passable:
+                return False
+        return True
     
     @staticmethod
     def __coordsToInt(x, y, width):
         return x + y * width
                     
-    def coordsToInt(self, x, y, width = -1):
+    def coordsToInt(self, x: int, y: int, width = -1):
         if width < 0:
             return x + y * self.dimensions[0]
         else:
             return x + y * width
             
-    def intToCoords(self, pos):
+    def intToCoords(self, pos: int):
         return pos % self.dimensions[0], int(pos / self.dimensions[0])
         
     def getThingAtCoords(self, x, y):
@@ -747,7 +857,7 @@ The closeEnough parameter will create a path that lands beside the source if nec
                 ret.append(self.things[i])
             return ret
         else:
-            return None
+            return []
             
     def getThingByName(self, name):
         if name in self.thingNames:
@@ -762,7 +872,7 @@ The closeEnough parameter will create a path that lands beside the source if nec
                 ret.append(self.things[i])
             return ret
         else:
-            return None
+            return []
             
     def getThingByID(self, thingID):
         if thingID in self.things:
@@ -806,7 +916,7 @@ The closeEnough parameter will create a path that lands beside the source if nec
                 ret.append(self.removeThingByThing(self.things[i]))
             return ret
         else:
-            return None
+            return []
             
     def removeThingByName(self, name):
         if name in self.thingNames:
@@ -821,7 +931,7 @@ The closeEnough parameter will create a path that lands beside the source if nec
                 ret.append(self.removeThingByThing(self.things[i]))
             return ret
         else:
-            return None
+            return []
             
     def removeThingByID(self, thingID):
         if thingID in self.things:
@@ -845,7 +955,9 @@ The closeEnough parameter will create a path that lands beside the source if nec
                 self.thingPos[newPos] = [name]
             else:
                 self.thingPos[newPos].append(name)
+            relPlayerx, relPlayery = thing.playerx - thing.x, thing.playery - thing.y
             thing.x, thing.y = x, y
+            thing.playerx, thing.playery = thing.x + relPlayerx, thing.y + relPlayery
         else:
             raise RuntimeError("There is nothing to move.".format(name))
             
diff --git a/testing/testDialog.yml b/testing/testDialog.yml
new file mode 100644
index 0000000..80dabcf
--- /dev/null
+++ b/testing/testDialog.yml
@@ -0,0 +1,15 @@
+%YAML 1.2
+---
+# This is a sample dialog tree, represented as nested dicts in YAML.
+opener: Hello, I'm a sample-dialog NPC. I assure you, I eventually turn
+    out to be a really well-rounded character.
+action: answer
+answers:
+  - Okay.
+  - Really? Well, tell me more!
+replies:
+  - opener: Yup.
+    action: exit
+  - opener: I would, but there's still a bunch of foreshadowing and stuff we
+        have to get through first.
+    action: back