Okay, the first horse chase in AC3 was god-awful. The optional requirement, to shoot all powder carts, is pretty much impossible due to the mechanics- your character will occasionally not fire his gun for some unfathomable reason while you ride, and if you slow down to shoot you lose your chase target. On top of that, the gun takes forever to reload because it's a flintlock, so if you miss or he targets a random enemy instead, you're bit going to get it in time to keep up the chase. I'm loving the game, but that part was abysmal.