I got a buddy who is completely new to 3.5/PF so we decided to start him out with a fighter, he picked a scythe as his primary weapon for maximum edge. I'm optimizing him for heavy hits, trips and AOOs. So far the build strategy uses Vital Strike with Felling Smash(DM allows them to function together) to get a trip attempt as a swift action, thus getting an AOO when he successfully trips the target from Greater Trip. There is a feat named Vicious Stomp that will give you an AOO when an adjacent foe falls prone BUT the attack has to be an unarmed strike. A very fun and cool feat, I was going to have him invest in monk a little to justify this feat but I'd rather not overwhelm him. Should I just abandon the feat and pursue something else or is there a way to get a large unarmed strike without veering away from Fighter?