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 :

• Universal Backpack

  Increase healing power of scrolls by 100%. Each turn recover 140 HP.
• Soul Capturing Hammer

  Recover self 2% HP, reduce 3% damage taken.
• Book of Slate

  Decreases Max. HP by 1% and Increase Max. CP by 10%. Increase 3% purify chance.
• Spartan Shield

  Restore 100 HP every turn. Reduce damage taken by 5%.
• S14 Profound Tentacles

  35% chance to restrict enemy who attack user for 1 turn. (Restriction) target will not be able to use any skills.
• Chakra Magatama

  Increase 2% accuracy.
  Additional 5 HP damage upon all attack.
• Star Dawn Harp

  Increases users agility by 1. Recover CP after HP reduction. (Amount: 10% of HP reduction) Recover HP by 2% when being put on a debuff.
• Father's Heart

  Reduce damage taken by 6%.
• Crimson Lanterns

  Increase attack damage by 6%. Has 6% chance to convert damage taken to HP positively.
• Three-stringed Lute Guitar
• Scroll: Yinyang Seal
• Wings of Eternal Eclipse

  Increases critical chance by 3%. Ignores 6% of the targets dodge rate.
• S17 Scorching Sun Scroll

  Has 30% chance to absorb 1% HP of enemy who attack you.
• Hanami Taiko

  2011 Hanami Festival - Rhythm! Recover HP & CP by 10 every turn.
• Dark Blade

  Increase 2% critical rate and ignore 2% of targets dodge.
• Golden Torch of Zeus

  Recover 150 HP every turn
• Dark Secret Seal

  Increases critical chance by 4%. Has 12% chance to Restrict anyone who attacks the user.
• S13 Kishu Twin Blades

  Increase accuracy by 8%
• Mischievous Candy

  Increase accuracy by 3%. Increase healing power of scrolls by 50%.
• MegaJingleBell

  A glorious Christmas artifact which can be used in battle. Ignores 5% of enemys dodge rate. Recovers 2% of users max HP every turn.
• S2 Demons erosion

  Recovers 4% of the users max HP every turn. Additional 100 damage on all attacks.
• Puppet: Hakuki (7 Days)

  Increase 3% accuracy.
  Reduce 46 HP damage taken.
  Recover 83 HP when each turn start.
• Bear of Affection

  Increase dodge rate by 3% and ignore target dodge by 3%.
• S78 Wandering Soul

  Recover CP after HP reduction. (Amount: 15% of HP reduction) Recover 15% extra CP when charge.
• Christmas Deer

  Increase critical chance 2% and critical damage 6%.
• Senior Kari Bagpack

  Reduce 3% damage taken.
• Assault Kite

  Recover 100 HP and 80 CP at the start of every turn.