You might as well compare with these Back Items so you can decide which Back Items you're gonna use for ninja Saga Pvp or in Hunting House for easier killing the boss or your opponent in ninja saga PvP
These Back Items might have better effect . Here we go :

• Tail of Jyubi

  Forged with chakra of the legendary tailed beast, Jyubi. Increase attack damage by 15% but reduce max. CP by 30%.
• Musashi Twin Blades
• Genin backpack (Blue)

  Double mission XP reward in level 11 to level 20.
• Sack of Hearts

  Cupids sack of hearts. Recovers 3% HP every turn. Has 5% chance to convert any damage to HP.
• Justice and Freedom

  Flag of the United States of America which symbolizes freedom and liberty. Recover 3% HP with every charge. Increases critical rate by 3%. Reduces damage taken by 50.
• S44 Earth Caller

  Increases attack damage by 4% and max HP by 5%.
• Triple Taiko

  Increases Max. HP by 4% and healing power of scrolls by 100%.
• Water Energy Skis
• GM Goldfish

  GM Goldfish
• Extra Large Presents Bag

  A large present bag, but nobody knows what it contains.
• Scroll: Terminated Rock
• Love Missile

  Additional 60 HP damage upon all attack.
• Straw Hat

  Increase dodge rate by 3%.
• Deadwood Pipa
• S10 Frostguard's Bow

  A magical bow that has a very long range. Reduce target 8% CP on every weapon attack.
• Red Ukiyo-e Kite

  4% chance to convert damage taken to HP positively and increase max. HP by 2%.
• Turkey Balloon

  Reduce damage taken by 7%. Recover 10% extra CP when charge.
• Spartan Shield

  Restore 100 HP every turn. Reduce damage taken by 5%.
• Gunbai: Gyoji
• Frost Soul Electric Guitar
• Orange Koi
• S12 Golden Bujin Jitte

  Increase dodge rate by 10%.
• Shadow Twin Blades
• Flour Stick
• Flame Soul Electric Guitar
• Gummy Bear

  Restores CP by 2%. Reduce damage taken by 100.
• Gruidae Wing

  Each turn recover 80 CP. Recover CP after HP reduction. (Amount: 8% of HP reduction)