A lot of DeFi combine earning with fun. I've come across dCity - a card game based on HIVE blockchain. Having read a great tutorial for dCity beginners, I've decided to give it a go. See my post on PeakD which shows my city (@merthin) on its Day 1.
Note
This is not a get-rich-quick scheme. If you treat it as an investment, it's definitely mid- to long-term. If you treat it like a game, be aware that it's not free - you will need to buy some HIVE to get started.