Luffy with Gear 5 is probably one of the strongest characters in One Piece at the moment. However, Gear 5 itself also has weaknesses, so enemies “like this” can completely make it difficult for the Straw Hat captain.
1. Swordsmen, or enemies that can make sharp attacks
Right from the beginning of the series, Luffy was able to easily resist gun attacks but was “weak” against sharp attacks. Until Luffy achieved Gear 5 status, this weakness persisted.
From there, very strong swordsmen like Mihawk or Shanks can fully take advantage of this weakness against Luffy. Those who are not swordsmen but can deliver sharp attacks can also be a threat to Luffy.
2. The user of the power of fire, magma and the like
Luffy can still be outdone with heat attacks. Enemies whose power is fire or magma will have a chance to outrun Luffy.
If it is fortunate that Sabo – who ate Mera Mera no Mi is Luffy’s brother, then Sakazuki – who has magma power is Luffy’s potential formidable enemy. With his Devil Fruit powers, Sakazuki is able to counter Luffy’s Gear 5.
3. Those who can nullify Devil Fruit powers
Luffy’s Gear 5 is very powerful. But if Luffy’s Gomu Gomu no Mi powers are disabled, he can’t use Gear 5. So Luffy must be careful against enemies who can “take away” his powers.
Therefore, Blackbeard with the ability of the Yami Yami no Mi fruit can also be a unique challenge for Luffy.
4. Characters with very high Haki
Luffy’s Conqueror Haki is very powerful, and now he can even add it to his attacks. If he had to fight Haki, an adversary whose Haki level was not inferior to Luffy’s could also be a difficult challenge.
Currently, the characters that are said to have powerful Conqueror Haki are Rayleigh and Shanks.
A long time ago, in episode 65 of SBS, someone asked Oda: “If Luffy’s Conqueror Haki can affect 50,000 people, how many can Shanks?”.
Oda then replied, “In a similar situation, Shanks and Rayleigh could affect 100,000 people”.
Currently, Luffy’s strength level seems to be close to that of Rayleigh and Shanks. But Oda’s answer seems to indicate that in the Fish-Man Island storyline, Shanks and Rayleigh’s Conqueror Haki is still far ahead of Luffy. Which means Luffy can still lose if he fights Haki with someone like that.
5. Enemies have high endurance
Luffy’s Gear 5 seems to have a time limit to use. In chapter 1045, there is a moment when Luffy suddenly “breaks out” of his Gear 5 form and looks like an old man.
But thanks to the drum of freedom – Luffy’s heartbeat, the captain of the Straw Hat Pirates was able to restore Gear 5 state again. But the situation unfolding in chapter 1045 shows that if the fight goes on for too long, Luffy can suddenly emerge from his Gear 5 form again.
So a strong and durable enemy could cause trouble for Luffy. Currently, Blackbeard and Akainu both feel like formidable enemies. For example Akainu can fight Kuzan for 10 days in a row and win.
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