Put some muscles into it. And hit on at least three different spots of the cups to try and knock it loose. If you still can't do it. Bike shop is the best bet.
Mine was really hard to get out, and I did it at a bike shop. But pretty much just keep working at it and try to put it somewhere where it's solid so your full force goes to the cups.
what you need: a brain and muscles, probs a hammer and chisel too, tap in a few spots as josh said and it should work if not hit head against wall and do us a favor