It takes about 3-4 hours to complete 1 refferal. But the good thing is is that if you install VirtualMachine you can run several League of Legends clients on 1 computer and still be able to fully use your computer while botting.
I get around 10-15 referals per day without doing anything because of the bot
So its just an extra and for each referal you get a 4 win IP boost so thats a 40 win IP boost each day without doing any effort.
