It is done with packet editing, I think it is like that: Opponent is sending a packet of BOTRK activation, you can do the same with hp potions, wards (I think with every activation item) server checks items activation but there is a little bug which lets you to bypass it. I think it is everything. Experienced person makes script in .lua with packet function (Bot of Legends lets you to makes such a scripts) and they can easily abuse this exploit. I don`t know how exactly to do that because I`m not experienced in packets editing. That would be cool if I helped someone with this post who actually can edit packets and he would share this method with me. Sorry for my bad grammar, I hope you can understand me.