compressing some games (mostly, VNs) that I either played already or I would play later to store on backup drive

Some compress pretty bad, like 95% ratio, I don't even bother waiting and just use plain TAR for them.

But some... listen, if zstd on fast settings can compress your game like 2-3x times, you're doing bad job at compressing assets. And that's VNs, mostly pictures and sometimes voice if we're lucky.