One Month of Sign-In at Impel Down: Ace Is Invincible at Marineford

He transmigrates into the world of One Piece.

By chance, he transmigrates as Portgas D. Ace.

Ace is rather frustrated about it, but fortunately, he is still in Impel Down.

He hasn't been taken to the execution ground to be put to death in front of the whole world.

But with his current strength, there's clearly no way he can change what happens in the Summit War.

Luckily, he activates a sign-in System.

As he keeps signing in with the System,

Ace acquires things from the Myriad Worlds, including the Wood Release kekkei genkai, the Sharingan, and a Zanpakuto.

He uses Kotoamatsukami to control Magellan, the warden of Impel Down.

A month later, the day of the execution arrives.

Ace looks at the Navy's three Admirals and the Whitebeard Pirates, who have come to rescue him.

He's going to defy fate and completely change the tragic destiny Ace originally faced.

One blow, Giant Buddha at the Summit, sends Roger flying.

Ryujin Jakka defeats the Navy's three Admirals.

One slash beheads Akainu.

At that moment, the Navy falls into despair. They know it now.

Roger's son, Ace, is invincible at Marineford.

This novel and its characters are entirely fictional. Any resemblance is purely coincidental. Do not imitate.