Ok so I spent an entire day asking around where to find the best proxies for league of legend cracking.
So many people told me fine proxy, but after asking around I was told they are slow / didn't work anymore as they may have been banned.
A friend let me test proxies that he had bought from Stormproxies, And they worked SO well. I have 3000 combo/minute and made so much more progress, , I highly recommend you invest in storm proxies as from first hand experience I say they work 100%.
Something I have learned from grinding is cracking isn't free. public proxies are slow / pointless to use.