diff --git a/pyproject.toml b/pyproject.toml
index edfb0d1..f84c314 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -25,7 +25,7 @@ dynamic = ["version"]
 
 [project.optional-dependencies]
 # Update dependencies in `all` if any are added or removed
-testing = ["pettingzoo[all]>=1.23.1", "pytest", "pytest-xdist", "stable-baselines3>=2.0.0", "moviepy >=1.0.0"]
+testing = ["pettingzoo[all,atari]>=1.23.1", "AutoROM", "pytest", "pytest-xdist", "stable-baselines3>=2.0.0", "moviepy >=1.0.0"]
 
 [project.urls]
 Homepage = "https://farama.org"