TwilioQuest

TwilioQuest is an educational retro-style video game that teaches a wide variety of programming skills including Javascript, PHP, Python, Git, and more.

https://www.twilio.com/quest

"Learn to code and lead your intrepid crew on a mission to save The Cloud in TwilioQuest, a PC role-playing game inspired by classics of the 16-bit era. Free forever, and available now for Windows, Mac, and Linux."