How do I beat kagemaru on the last dule and how do I get a strong deck..

Kagemaru is dang easy all you have to do is counter the deck he is using like first he will use a hamon deck so try to pack spell card removers like heavy storm but don't pack too many just let him summon hamon and use a trap to kill it... Beware he has 2 more hamons left so once you kill hamon keep your spell removals to kill the continus spell cards he is going to use.

Next his is uria deck, just keep a deck with a ace in the hole(for me it was master of dragon slodier ATK 5000/DEF500 gains 500 for each dragon type on your field) because if you use the same deck that you used against hamon and keep destroying his traps and once he gets it on the field he is going to be power mad, I did that and I had to killl him off at 9000ATK! That is using united we stand on my ace and 4 dragon monsters on the field! So just pack some monster removal like fissure or sakuretsu armour and if you don't want to use those use wall of revealing light to stop him as long you don't kill of his traps

Lastly there is is big and powerful Raviel, just let him summon it and use monster removal but be sure to pack good monsters like vorse raider and use combos like stop defense and fissure because this combo can kill any facedown defence card he has on

Get a good deck with plenty of sakeretsu armors, drain shields, and high level monsters, and stuff that you can destroy the sacred beats with.

Hi,in order to beat Kagemaru,you need to allow him to summon the Sacred Beast and then counter it with a card that can help you destroy it.For example,let him summon Raviel,Lord of Phantasms and then destroy it with Exile of the Wicked.

Also,destroy Uria,Lord of Searing Flames by using Soul Release to remove up to 5 Continuous Traps in his graveyard.

Destroy Hamon with Ring Of Destrustion