Magic number

450 XP

Solved by 35 users:

5lash,  adhie,  andrewxxtheone,  anon1234,  asdasd,  balsa0,  blackaura,  BlueCode,  brianm,  crlupin,  Csq,  dietmar,  frecarl92,  Gaben007,  gobi,  hauptbenutzer,  Hydro,  isserp,  jajce,  KitKett,  kmate,  lorizje,  magicrc,  misi444,  mza8202,  Nirmona,  normynation,  Reuben,  sbr2015,  sitnikov,  SlipOne,  stribika,  szabto,  typjtk,  vezerb,