diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..4a96c22
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+source .venv/bin/activate
\ No newline at end of file
diff --git a/__pycache__/asteroid.cpython-311.pyc b/__pycache__/asteroid.cpython-311.pyc
new file mode 100644
index 0000000..24582d5
Binary files /dev/null and b/__pycache__/asteroid.cpython-311.pyc differ
diff --git a/__pycache__/asteroid_spawner.cpython-311.pyc b/__pycache__/asteroid_spawner.cpython-311.pyc
new file mode 100644
index 0000000..dd47076
Binary files /dev/null and b/__pycache__/asteroid_spawner.cpython-311.pyc differ
diff --git a/__pycache__/spaceship.cpython-311.pyc b/__pycache__/spaceship.cpython-311.pyc
new file mode 100644
index 0000000..84416fc
Binary files /dev/null and b/__pycache__/spaceship.cpython-311.pyc differ
diff --git a/asteroid.py b/asteroid.py
index 257354b..cfd811f 100644
--- a/asteroid.py
+++ b/asteroid.py
@@ -2,3 +2,23 @@
 # ------------
 # By MWC Contributors
 # This module defines an asteroid agent class.
+
+class Asteroid:
+    character = "0"
+
+    def __init__(self, position):
+        self.position = position
+
+    def play_turn(self, game):
+        width, height = game.board_size
+        if game.turn_number % 2 == 0:
+            x, y = self.position
+            if y == height - 1:
+                game.remove_agent(self)
+            else:
+                ship = game.get_agent_by_name('ship')
+                new_position = (x, y + 1)
+                if new_position == ship.position:
+                    game.end()
+                else:
+                    self.position = new_position
\ No newline at end of file
diff --git a/asteroid_spawner.py b/asteroid_spawner.py
index 92e542d..5e576bd 100644
--- a/asteroid_spawner.py
+++ b/asteroid_spawner.py
@@ -2,3 +2,19 @@
 # -------------------
 # By MWC Contributors
 # This module defines an AsteroidSpawner agent class.
+
+from random import randint
+from asteroid import Asteroid
+
+class AsteroidSpawner:
+    display = False
+
+    def play_turn(self, game):
+        width, height  = game.board_size
+        game.state['score'] += 1
+        if self.should_spawn_asteroid(game.turn_number):
+            asteroid = Asteroid((randint(0, width - 1), 0))
+            game.add_agent(asteroid)
+    
+    def should_spawn_asteroid(self, turn_number):
+        return randint(0, 1000) < turn_number
\ No newline at end of file
diff --git a/nav_game.py b/nav_game.py
index 191d83d..2225687 100644
--- a/nav_game.py
+++ b/nav_game.py
@@ -2,3 +2,13 @@
 # ------------
 # By MWC Contributors
 # This class implements a simple game where a spaceship avoids asteroids.
+
+from retro.game import Game
+from spaceship import Spaceship
+from asteroid_spawner import AsteroidSpawner
+
+board_size = (25, 25)
+ship = Spaceship(board_size)
+spawner = AsteroidSpawner()
+game = Game([ship,spawner], {"score": 0}, board_size=board_size)
+game.play()
\ No newline at end of file
diff --git a/poetry.lock b/poetry.lock
new file mode 100644
index 0000000..afc5112
--- /dev/null
+++ b/poetry.lock
@@ -0,0 +1,81 @@
+# This file is automatically @generated by Poetry 2.3.1 and should not be changed by hand.
+
+[[package]]
+name = "ansicon"
+version = "1.89.0"
+description = "Python wrapper for loading Jason Hood's ANSICON"
+optional = false
+python-versions = "*"
+groups = ["main"]
+markers = "platform_system == \"Windows\""
+files = [
+    {file = "ansicon-1.89.0-py2.py3-none-any.whl", hash = "sha256:f1def52d17f65c2c9682cf8370c03f541f410c1752d6a14029f97318e4b9dfec"},
+    {file = "ansicon-1.89.0.tar.gz", hash = "sha256:e4d039def5768a47e4afec8e89e83ec3ae5a26bf00ad851f914d1240b444d2b1"},
+]
+
+[[package]]
+name = "blessed"
+version = "1.27.0"
+description = "Easy, practical library for making terminal apps, by providing an elegant, well-documented interface to Colors, Keyboard input, and screen Positioning capabilities."
+optional = false
+python-versions = ">=3.7"
+groups = ["main"]
+files = [
+    {file = "blessed-1.27.0-py3-none-any.whl", hash = "sha256:1c599969acc993bb5842bf3f638b0691e335277a9d9058cd079463a346988714"},
+    {file = "blessed-1.27.0.tar.gz", hash = "sha256:e3064559388bd532ab6460d9b6c7d6dd699c4e0cf54d28ed6e2cab12feda13bb"},
+]
+
+[package.dependencies]
+jinxed = {version = ">=1.1.0", markers = "platform_system == \"Windows\""}
+wcwidth = ">=0.2.14"
+
+[package.extras]
+docs = ["Pillow", "Sphinx (>3)", "sphinx-paramlinks", "sphinx_rtd_theme", "sphinxcontrib-manpage"]
+
+[[package]]
+name = "jinxed"
+version = "1.3.0"
+description = "Jinxed Terminal Library"
+optional = false
+python-versions = "*"
+groups = ["main"]
+markers = "platform_system == \"Windows\""
+files = [
+    {file = "jinxed-1.3.0-py2.py3-none-any.whl", hash = "sha256:b993189f39dc2d7504d802152671535b06d380b26d78070559551cbf92df4fc5"},
+    {file = "jinxed-1.3.0.tar.gz", hash = "sha256:1593124b18a41b7a3da3b078471442e51dbad3d77b4d4f2b0c26ab6f7d660dbf"},
+]
+
+[package.dependencies]
+ansicon = {version = "*", markers = "platform_system == \"Windows\""}
+
+[[package]]
+name = "retro-games"
+version = "1.1.3"
+description = "A simple framework for Terminal-based games"
+optional = false
+python-versions = "<4.0,>=3.10"
+groups = ["main"]
+files = [
+    {file = "retro_games-1.1.3-py3-none-any.whl", hash = "sha256:4bdd27241b5cb3ee72e69a042d301ff58df2a2ade7e3c29400a538fa54e30148"},
+    {file = "retro_games-1.1.3.tar.gz", hash = "sha256:4f91ff725e551820aa4e30c12c0264e2da41967ed34252122b7136bc2a8ed311"},
+]
+
+[package.dependencies]
+blessed = ">=1.20.0,<2.0.0"
+
+[[package]]
+name = "wcwidth"
+version = "0.3.5"
+description = "Measures the displayed width of unicode strings in a terminal"
+optional = false
+python-versions = ">=3.8"
+groups = ["main"]
+files = [
+    {file = "wcwidth-0.3.5-py3-none-any.whl", hash = "sha256:b0a0245130566939a24ab8432e625b38272fbc62ecbe5aecbdcb50b8f02ce993"},
+    {file = "wcwidth-0.3.5.tar.gz", hash = "sha256:7c3463f312540cf21ddd527ea34f3ae95c057fa191aa7a9e043898d20d636e59"},
+]
+
+[metadata]
+lock-version = "2.1"
+python-versions = ">=3.10,<4.0"
+content-hash = "03cc38c17964eb2c920ecf014cbfcf966c0c719418a127947b33382f086a0a6e"
diff --git a/spaceship.py b/spaceship.py
index 9f3552a..1b334c7 100644
--- a/spaceship.py
+++ b/spaceship.py
@@ -2,3 +2,24 @@
 # ------------
 # By MWC Contributors
 # This module defines a spaceship agent class.
+
+class Spaceship:
+    name = "ship"
+    character = '^'
+
+    def __init__(self, board_size):
+        board_width, board_height = board_size
+        self.position = (board_width // 2, board_height - 1)
+
+    def handle_keystroke(self, keystroke, game):
+        x, y = self.position
+        if keystroke.name in ("KEY_LEFT", "KEY_RIGHT"):
+            if keystroke.name == "KEY_LEFT":
+                new_position = (x - 1, y)
+            else:
+                new_position = (x + 1, y)
+            if game.on_board(new_position):
+                if game.is_empty(new_position):
+                    self.position = new_position
+                else:
+                    game.end()