Okay, I'm on the part where you have to get that one Digimon's mask,the..

You need to go back to Asuka city. The person that has it is in the Etemon suit. If you talk to everybody ;in that city you will eventually bug him enough to where he will just give the mask to you. Then you go to Sepikmon, give him his mask back and he will give you the smelly herb. Use it on the Giant horse guy and he'll run away. When you go to the jungle shrine you'll fight him there and get a rusty katana and some bit. Hope this helped you.!!!

To beat the Zambamon in the graveyard you first must battle him then when your Digimon have run away you have to go to Shaman house and talk with the Digimon with the bag over his hed(Sepikmon). After you've talk to him go to Baronmon(in Protocol ruins) he will tell you that Sepikmon lost his mask in Asuka city so go there. When you get to Asuka Bridge go a litle right at the gate to Asuka city and you will find a Digimon there, he will say that he is Sepikmon and he will not tell you how to beat Zambamon. First go to Divermon's Lake and talk to a man in black( go to the area where there is a lot of trees and go through the hidden path and you'll find him). After talking to him go into Asuka city and talk to Etemon( where the old people were saying that they wanted to become Digimon). After that go to the sewers(just go to Asuka Inn and go to the underground and down the ladder) you will find Etemon there, talk to him and he will give you Sepikmon's mask. Go back to Shaman house and talk to the real Sepikmon he'll give you a Smelly Herb and then go to Zambamon in the graveyard and talk to him then you will take out Smelly Herb and "he" will run away this time after that you can go further.