No caus they log every payment and you only get the gold if there system says payment acept else you get ingame payment failed message.
I also look for an hack since a year...
I know it is possible.
For true its a serversidet game but i have seen players who leveld heros from 1 to 100 in a day.
I know there was an hack at world of warcraft with it you can double your damage and exp maybe someting like that is also possible at that game.
I am no programmer but maybe anyone can do someting like that. Cause you do not need gold the only thing you need are strong heros and gems.