A ton of ads but you get stuff for letting the ads play. The game has a lot of cool facets and is not a pay to win game. EDIT: Had rated this 5 stars but then app started having issues. Had paid for the $19.99 subscription also. Uninstalled and reinstalled the app hoping the app issues would go away. Lost ALL of my progress and lost my subscription. Even used the facebook sign in but the progress is lost.