Flame
Ace sat on the beach of the nameless island he'd reduced to ash and slag while experimenting with his Devil Fruit Ability, eating the food Fox had brought over. They'd been here for a week now and while he was quickly getting the hang of his limits and how to control how much flame he emitted at a time, he wasn't any closer to understanding why his powers had changed so drastically. His lover –and wasn't it both so odd and so wonderful to think of Fox that way– sat opposite him, a cushion protecting her from the glass and deformed rock he had reduced the once-sandy expanse to.
"What're you brooding over, Kajin?" Ace glanced over at the snowy-haired woman again and grinned.
"Hey, what makes you think I'm brooding, hm Kitsune? I could be imagining what I'm going to do to you in bed now I don't need that damn shackle to keep the fire under my skin!" It had been humiliating to have to rely on Sea Stone to keep himself from accidentally immolating her, but that was past now.
"Nice try," Fox said dryly, "but you've got this little furrow between your eyebrows that says you're brooding. Spill; or do I have to coax it out of you?"
"I wouldn't say no to coaxing," Ace leered.
"Don't change the subject Kajin," Fox said calmly. "You're bothered about something. Either you tell me now or I go rooting around for it later."
"Fine, fine," Ace raised his hands in surrender. "I just don't understand why my powers have suddenly changed. It doesn't make sense! Devil Fruit is what it is, so how come mine is so different all of a sudden?"
Fox shifted on her cushion. "Edward D. Spadille, my darling Kajin, what is flame?"
Ace stared at her. "It's fire, of course."
"So what is fire?" Ace shifted under that steady, expectant gaze.
"Er, hot? How things burn?" he ventured.
"You never had any kind of schooling really, did you?"
"No," Ace muttered grumpily. It wasn't like he was ignorant or anything! He had fantastic survival skills and was a great fighter! He could read, write, do sums, sail and navigate so what else did he need?
"Easy there Kajin; it wasn't a put-down," Fox said gently. "I forget sometimes that most people don't have my education; my father taught me more than most people realise exists."
"Mihawk taught you?"
"Oh yes; he drilled me relentlessly and gave me things to memorise and think about even when he wasn't going to be there," Fox admitted. "I'm a compulsive learner even now." She paused. "Back to the subject: flame is visible heat."
"Huh?" That just did not make sense.
Fox produced a sturdy candle from the picnic basket, lit it and set it on a saucer. "Is the flame any hotter than the air above it? Or around it?"
Ace poked the flame experimentally. The air immediately above it was in fact just as hot as the flame itself. A little more investigation proved the bottom of the flame was in fact rather cool.
"You've seen things spontaneously combust, haven't you?" Fox asked.
"Yeah." Piles of damp leaf litter in the jungles back on Dawn Island had done that occasionally on hot days. He had no idea why or how though.
"If a thing that has the potential to burn gets hot enough it will burst into flames," Fox said, "because flames are the visible manifestation of heat. Conversely, things can also burn without ever giving off visible flames."
Ace nodded; everything made sense so far but what did that mean to him?
"So, Kajin: you ate the Flame-Flame Fruit. What are you made of?"
"Visible heat…" Ace trailed off. There was a lot more to heat than there was to fire. Steel didn't burn, but heat melted it. He'd once seen people collapse after getting too close to a furnace. Heat distorted the air to create mirages, as he'd seen recently on Alabasta. Heat affected everything, even things that didn't burn.
"You get it now?" Ace grinned.
"I think so. But if I've always been able to do this stuff, why haven't I found out before?"
"Did you experiment? I mean seriously experiment, like find out how hot you could get your flames, how far you could expand your area of influence, the differences between being partially transformed and fully transformed?"
"Not really," Ace admitted sheepishly. He'd mostly been interested in how he could set things on fire. What she said sounded worth investigating though.
"There you go then."
"But why now?"
Fox sighed. "Do you know why Sakazuki was able to hit you?"
"Who?"
"Admiral Akainu's real name is Sakazuki."
"Oh; he said lava was superior to flame-"
Fox snorted. "You actually listened to the garbage he was spewing? I just ignore him on principle; he's a fanatic, a hypocrite and not worth wasting time on. Listen: flame is insubstantial. You just put your finger through that candle flame; it has no mass. It is weightless. It is a visible manifestation of heat and you can't hit heat; there's nothing to hit."
"Then how did he hit me?"
Fox sighed. "Ace, you favour a physical fighting style. This means that when you are fighting you cannot be in your full Logia form as your hits would go right through people. You'd probably leave nasty third-degree burns, but you wouldn't feel any impact and neither would they. I think you automatically suppressed your Devil Fruit Ability when you fought so it only affected your skin, that way your muscles and bones could still land physical hits. When you hit Sakazuki the flames did not affect him as your Logias are complementary, but as you were only partially transformed he damaged the underlying tissue you were trying to hit him with."
Ace could visualise how that would be possible. "So when I tried to protect Luffy..." he trailed off.
"Flame is insubstantial; bullets do go right through you," Fox said gently. "You blocked that blow with your physical body while suppressing your Devil Fruit as much as possible. Otherwise he'd have gone through you like you weren't there."
Ace blanched and shivered. Knowing that was so, so much more frightening that just thinking he'd been unlucky in his opponent.
"You'd have been better off trying to shove Luffy out of the way," Fox mused idly, "but hindsight is not helpful at this juncture. Anyway, you got very badly injured and almost died, though you can't really remember it. Your subconscious however remembers it perfectly, as does your body and neither want to go through that ever again. So your Devil Fruit Ability is now being tapped much more heavily so that when you perceive any kind of threat you automatically assume your Logia form from the inside rather than from the outside like you did before. Rather than remaining in a layer under your skin the flames are now coming from your core."
"So this is what the Fruit was supposed to make me into, but I was ignoring it," Ace summarised, "and now I can't ignore it anymore."
"Basically," Fox agreed. "Remember that flame is insubstantial, so you cannot stand in front of people and defend them; it just won't work as fire has no defensive properties. You have to attack your enemies and do so relentlessly: fire is a purely offensive ability. Your enemies won't be able to touch you, but you can't physically touch them either."
"But, that's my whole fighting style!" Ace protested.
Fox watched him steadily from under her lashes. "How did Blackbeard beat you?"
"He touched…" Ace trailed off. "I hate you and your logic. Why do you always have to be right?"
"It doesn't have to be anything more complicated than gloves or knuckledusters," Fox pointed out mildly, "and once you've got the hang of your Devil Fruit I can teach you more about haki, which will give you all the defensive power you could possibly desire as well as enable you to land hits."
"Tricky Kitsune," Ace muttered, smirking appreciatively. "I can use a bo staff too."
"We'll find someone capable for you to spar against, Kajin," Fox said. "In the meantime I'll teach you some Fishman Karate stances. You won't be able to throw water with them, but with a bit of playing around you should be able to use the framework to throw fire."
"Ooh, nice." Ace knew exactly how powerful Fishman karate could be; he'd fought Jinbe to a standstill once. He also recognised adding some formal training would be very helpful towards improving his own instinctive brawling style.
"I recognise that I can't stop you from wanting to beat people in the ground," Fox said teasingly, "but this way you can do so without leaving gaping holes in your defences."
Ace chucked a plum stone at her; she ducked it. "What did you mean when you said my Ability was complimentary to Sakizuki's?" he asked.
Fox grinned. "Lava is molten rock, which in nature is frequently on fire. So if you'd been in full Logia form when he hit you, you would have just flowed around him without being harmed. You might even be able to walk right through him next time you meet him, though you certainly can't do each-other any harm with your respective Abilities."
Ace grinned, eyes glinting madly. He liked the sound of that so, so much! "That's what haki is for," he said maliciously. He was going to work himself into the ground to make this work!
"It is indeed," Fox agreed, smiling a little cruelly. "I'd suggest learning to use a blade of some kind too, just in case you run into Blackbeard."
Oh yes: Devil Fruit Abilities may not work on the traitor but blades would still cut him. Especially Sea Stone blades. Ace smiled. "Kitsune, my precious, my beloved?"
"What do you want, Kajin?"
Ace graced her with a pleading look. "Can I have one of your Sea Stone weapons? Pretty please?"
Fox stared flatly at him. "Not until you can prove to me you are capable of using a normal steel equivalent," she stated.
"I can live with that." He paused. "Is there anybody chasing after Teach now?"
"Not that I know of, but he's been blacklisted by the network so everyone who sees him will report him in and likely engage in a little recreational sabotage in the hopes of getting a bonus," Fox said cheerfully.
Ace brightened instantly; that sounded wonderful. "It couldn't have happened to a better person," the flame Logia said blissfully. "I wish I could see it."
A slower chapter, but still important. I always felt Ace was under-using his abilities compared to the admirals or even Crocodile.