diff --git a/dungeonbattle/entities/items.py b/dungeonbattle/entities/items.py
index 09750c7..3edec91 100644
--- a/dungeonbattle/entities/items.py
+++ b/dungeonbattle/entities/items.py
@@ -8,9 +8,9 @@ class Item(Entity):
         super().__init__(*args, **kwargs)
         self.held = False
 
-    def drop(self, x: int, y: int) -> None:
+    def drop(self, y: int, x: int) -> None:
         self.held = False
-        self.move(x, y)
+        self.move(y, x)
 
     def hold(self) -> None:
         self.held = True
diff --git a/dungeonbattle/entities/monsters.py b/dungeonbattle/entities/monsters.py
index f4a7a1f..59db0e7 100644
--- a/dungeonbattle/entities/monsters.py
+++ b/dungeonbattle/entities/monsters.py
@@ -2,7 +2,7 @@ from ..interfaces import FightingEntity, Map
 
 
 class Monster(FightingEntity):
-    def act(self, map: Map) -> None:
+    def act(self, m: Map) -> None:
         pass
 
 
diff --git a/dungeonbattle/interfaces.py b/dungeonbattle/interfaces.py
index 5d57510..6546523 100644
--- a/dungeonbattle/interfaces.py
+++ b/dungeonbattle/interfaces.py
@@ -66,12 +66,16 @@ class Tile(Enum):
 
 
 class Entity:
-    x: int
     y: int
+    x: int
 
-    def move(self, x: int, y: int) -> None:
-        self.x = x
+    def __init__(self):
+        self.y = 0
+        self.x = 0
+
+    def move(self, y: int, x: int) -> None:
         self.y = y
+        self.x = x
 
     def act(self, m: Map) -> None:
         """
@@ -85,9 +89,12 @@ class FightingEntity(Entity):
     maxhealth: int
     health: int
     strength: int
+    dead: bool
 
     def __init__(self):
+        super().__init__()
         self.health = self.maxhealth
+        self.dead = False
 
     def hit(self, opponent: "FightingEntity") -> None:
         opponent.take_damage(self, self.strength)
@@ -98,4 +105,4 @@ class FightingEntity(Entity):
             self.die()
 
     def die(self) -> None:
-        pass
+        self.dead = True
diff --git a/dungeonbattle/tests/entities_test.py b/dungeonbattle/tests/entities_test.py
new file mode 100644
index 0000000..f7d75f1
--- /dev/null
+++ b/dungeonbattle/tests/entities_test.py
@@ -0,0 +1,81 @@
+import unittest
+
+from dungeonbattle.entities.items import Bomb, Item
+from dungeonbattle.entities.monsters import Squirrel
+from dungeonbattle.entities.player import Player
+from dungeonbattle.interfaces import Entity, Map
+
+
+class TestEntities(unittest.TestCase):
+    def setUp(self) -> None:
+        """
+        Load example map that can be used in tests.
+        """
+        self.map = Map.load("example_map.txt")
+
+    def test_basic_entities(self) -> None:
+        """
+        Test some random stuff with basic entities.
+        """
+        entity = Entity()
+        entity.move(42, 64)
+        self.assertEqual(entity.y, 42)
+        self.assertEqual(entity.x, 64)
+        self.assertIsNone(entity.act(self.map))
+
+    def test_fighting_entities(self) -> None:
+        """
+        Test some random stuff with fighting entities.
+        """
+        entity = Squirrel()
+        self.assertIsNone(entity.act(self.map))
+        self.assertEqual(entity.maxhealth, 10)
+        self.assertEqual(entity.maxhealth, entity.health)
+        self.assertEqual(entity.strength, 3)
+        self.assertIsNone(entity.hit(entity))
+        self.assertFalse(entity.dead)
+        self.assertIsNone(entity.hit(entity))
+        self.assertFalse(entity.dead)
+        self.assertIsNone(entity.hit(entity))
+        self.assertFalse(entity.dead)
+        self.assertIsNone(entity.hit(entity))
+        self.assertTrue(entity.dead)
+
+    def test_items(self) -> None:
+        """
+        Test some random stuff with items.
+        """
+        item = Item()
+        self.assertFalse(item.held)
+        item.hold()
+        self.assertTrue(item.held)
+        item.drop(42, 42)
+        self.assertEqual(item.y, 42)
+        self.assertEqual(item.x, 42)
+
+    def test_bombs(self) -> None:
+        """
+        Test some random stuff with bombs.
+        """
+        item = Bomb()
+        squirrel = Squirrel()
+        self.map.entities.append(item)
+        self.map.entities.append(squirrel)
+        squirrel.health = 2
+        squirrel.move(41, 42)
+        item.act(self.map)
+        self.assertFalse(squirrel.dead)
+        item.drop(42, 42)
+        self.assertEqual(item.y, 42)
+        self.assertEqual(item.x, 42)
+        item.act(self.map)
+        self.assertTrue(squirrel.dead)
+
+    def test_players(self) -> None:
+        """
+        Test some random stuff with players.
+        """
+        player = Player()
+        self.assertEqual(player.strength, 5)
+        self.assertEqual(player.health, player.maxhealth)
+        self.assertEqual(player.maxhealth, 20)
diff --git a/dungeonbattle/tests/interfaces_test.py b/dungeonbattle/tests/interfaces_test.py
index 849e28b..d6ab078 100644
--- a/dungeonbattle/tests/interfaces_test.py
+++ b/dungeonbattle/tests/interfaces_test.py
@@ -1,6 +1,6 @@
 import unittest
 
-from dungeonbattle.interfaces import Map
+from dungeonbattle.interfaces import Map, Tile
 
 
 class TestInterfaces(unittest.TestCase):
@@ -12,3 +12,22 @@ class TestInterfaces(unittest.TestCase):
         self.assertEqual(m.width, 2)
         self.assertEqual(m.height, 2)
         self.assertEqual(m.draw_string(), ".█\n█.")
+
+    def test_load_map(self) -> None:
+        """
+        Try to load a map from a file.
+        """
+        m = Map.load("example_map.txt")
+        self.assertEqual(m.width, 52)
+        self.assertEqual(m.height, 17)
+
+    def test_tiles(self) -> None:
+        """
+        Test some things about tiles.
+        """
+        self.assertFalse(Tile.FLOOR.is_wall())
+        self.assertTrue(Tile.WALL.is_wall())
+        self.assertFalse(Tile.EMPTY.is_wall())
+        self.assertTrue(Tile.FLOOR.can_walk())
+        self.assertFalse(Tile.WALL.can_walk())
+        self.assertTrue(Tile.EMPTY.can_walk())