Raisins are required to get Year 2 Gjallarhorn. You have to eat them (box included) and if you do it while wearing the Xylar mask, they will digest in 1 hour. Then go to the Tower bathroom underneath the Speaker's Library, you should walk out with rainbow weapon parts. Turn them in to Xûr's sister and she'll give you the keys to get inside a secret room in the cosmodrome. Inside, a taxi will drive you out far away from the cosmodrome. The windows are tinted so you can't see outside. When you step out, there's Xûr's ship waiting for you. It takes you to the Nine's headquarters. You are greeted by the Nine, but all of them are wearing Bungie T-Shirts. You suspect somethings fishy, but they want to take all your strange coins in exchange for 1,000,000 silver, and a receipt. On your way back home, you see something printed on the receipt. It turns out to be a code, along with a map to where the code goes. It takes you to the building with the postmaster and Eververse, but you enter the code on a keypad in the unoccupied booth. You get inside, and you see a box made of steel. There's a coin slot inside. You have to individually put all 1,000,000 silver coins inside, and once you do, you get Year 2 Gjallarhorn.