8 if you watch Netflix, Twitch, Youtube or hear a podcast while playing it.
Its not pay to win at all and quiet balanced right now. It only has like 300 Cards right now, so I think it has great potential.
I played some MTGA when the beta came out but stopped because of all the pay to win and rng bullshit. I played runeterra for like 30 min and got bored, however, it seems like a middle ground between HS and MTG and a better economy (but that might change). also the client is already better than MTG.