[popcar2]

My friend, you just rediscovered Crazy Eights: https://en.wikipedia.org/wiki/Crazy_Eights

[madcaptenor]

In fact, Uno exists because one family liked playing Crazy Eights but got tired arguing about the rules, so they started writing the rules on the cards and eventually made new cards: https://www.museumofplay.org/toys/uno/