Eat ROS (reactive oxygen)

In this game, reactive oxygen (ROS) is generated when electron (e-) hits oxygen (O2). Because ROS is toxic to living things, we should detoxify ROS using activated enzyme. Inactive enzyme (blue color) is activated by hitting electron. ROS is eaten and detoxified when active enzyme hits ROS. The game score indicates the number of detoxified ROS by the time five electrons fall.