According to Capcom, Monster Hunter 4 Ultimate is getting a new free DLC this month. Below is a video which gives you more information about what it will be like. Also, you can see a list of the things included in the DLC, starting from the new quests added to the melodic set added, and other interesting things.

• 12 New quests (includes two New Arena challenges)
• Five New weapon
• A New complete armor set (GX Hunter)
• Four New Unique armor pieces
• A New Palico equipment set (Melodic set)
• One Bonus Palico: Oliver
• One Guild Card background
• Eight Guild Card titles

Monster Hunter 4 Ultimate was released in February and every month since then, Capcom released a free DLC, but the final one will come on November 6.

Source: VG247