You can save up to 75% on buying Microsoft RTS Collections which includes Age of Empires/Age of Mythology/Rise of Nations.
It includes the following games,
- Age of Empires II HD – Age of Empires II has been re-imagined in high definition with new features, trading cards, improved AI, workshop support, multiplayer, Steamworks integration and more!
- Age of Empires II HD: The Forgotten
- Age of Empires® III: Complete Collection – Microsoft Studios brings you three epic Age of Empires III games in one monumental collection for the first time.
- Age of Mythology: Extended Edition – Age of Mythology is back! Choose your god and take to the battlefield in this classic, upgraded with full Steamworks integration and enhanced features.
- Rise of Nations: Extended Edition – Rise of Nations is back! Play the updated classic with full Steamworks integration and enhanced features, including Twitch.tv streaming!
You can buy this collections for just $24.99.
Check out the deal here from Steam.