Ok, you need

Adamantine x1

Dragon Fang x4

Pulse Ammo x12

How to get it:

To get the Adamantine either defeat an Adamantoise
or change Minotaur card into item.

To get Dragon Fangs fight From Blue Dragon w/RARE ITEM ability on to receive it as a item

And finaly to get Pulse Ammo change Lazer Cannon item to get 5 Pulse Ammo or change Power Generator to get 20 Pulse Ammo.

Thats how I just did it.