Mac Client since 5.7 has been terrible.
The mac Client for LOL has been super screwed up since 5.7. Store doesn't work. When you launch a game it ALWAYS says there is a "Firewall Error" but every time I click retry it automatically works. The loads are UNGODLY long now, which makes no sense because I'm on 75/75 FiOS internet, with a new Macbook Pro, and a 2013 iMac. It used to take 15 seconds, now it's like 3-4 minutes. If i use my Surface(which has lower specs than the Macs, i loads in 25 seconds. Something is severely wrong with the Mac LOL Client. You know, we like League too Riot.....?