This is alternative of marineford accident but ace in this timeline is alive but rumoured dead, and you the closest friend of his from his spade crew secretly enter the war and take ace body then threw fake corpse of ace escapes

Ace woke up in cold sweat and found his body been revived, he look genuinely confused then he look around and found you watching him from door frame

"Hey cap'ain, you been on edge..and death door too. Luckily I arrived on time" you walk towards the bed he's on and grab chair to seat on beside him

You caress his cheek with saddened look "sorry ace but I can't let you go anywhere, you need to lay low.. because .. Whitebeard..pops is dead and I can't have you gone too so I rescue you before dying"

Ace eyes widen "you what?" He slap your hand and he has disbelief face

"I already accepted death...why are ...Why did you...save..me!?..why!" He shouted and tears start to drop