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 :

• GM back item
• Steel Frame Tail
• GM Goldfish

  GM Goldfish
• S17 Scorching Sun Scroll

  Has 30% chance to absorb 1% HP of enemy who attack you.
• Balloon Rabbit Doll

  Has 8% chance to convert damage taken to HP positively.
• S12 Ancient Blood Evil Gourd

  Increase max. HP by 5%. But reduce Max.CP by 1%.
• Scroll: Genbu
• Giant Copper Coins

  Increase Mission gold reward by 30%.(Mission Only)
• Hanagara Hagoita

  Increase max. HP by 3%.
• Shishimai Back

  Restores 3% of users max HP.Has 4% chance to convert damage taken to HP positively.
• Blood Brush

  Increase 3% damage and increase healing power of scrolls by 10%.
• First-Aid Kit

  100% of the purchase price will be donated to Japan earthquake relief.
• Crystal Ice Mirror

  5% chance to freeze enemy who attack user (1 turn). Frozen target cannot move but damage taken is reduced by 80%
• Python Scales Raijinco
• 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.
• Nightmare Grudge

  Ignore 4% targets dodge.
• Cupid Wing

  Increase critical chance 4% and critical damage 10%.
• Kettle
• Paper Envoy of God

  Increases attack damage and reduces damage received by 4%
• S15 Ancient Seitenken

  Recover CP after HP reduction. (Amount: 16% of HP reduction)
• Gunbai: World Peace
• Puppet: Hakuki (7 Days)

  Increase 3% accuracy.
  Reduce 46 HP damage taken.
  Recover 83 HP when each turn start.
• Tailed Beast Chakra Crystal

  Increase 3% damage.
  Reduce 3% damage taken.
  Recover 2% HP each turn start.
• 2011 Carnival Jiegu

  Ninja Saga 2nd Anniversary Carnival! Each turn recover 100 HP and 100 CP.
• Spirit Flag

  An inspiring banner that boosts the holders morale. Increase critical chance and dodge rate by 3%.
• Charming Aura (Red)

  2012 Valentines day limited aura, increase all damage 2%.
• Red Shuriken Skis