Questions about example sentences with, and the definition and usage of "Ggs"

A: Thank you.I was playing chess

A: ggs tho is just internet slang. Good game(s), though.

the s may or may not have been added on for plural. If not, then the s is pointless really.

I have never heard of good game slave, but perhaps I just don't know about it?

A: Ma cos’è??