Alchemy

Alchemy, 錬金 in Japanese and read Renkin, belongs to Valdo Gollini and appears in My Hero Academia: You're Next. It is an Emitter Quirk that triggers on contact.

Touch anything that is not alive and Valdo can rewrite what it is. The reach of that one sentence is what makes the power dangerous, because it covers weapons, terrain, machinery, his own face, and eventually a city sector lifted into the sky.

Any inanimate object under his hand becomes something else, from a simple bullet to a working drone that streams live video. The result need not stay solid, either. He can shift matter into water, or into a glowing kinetic state whose shockwaves flatten several buildings in a single swipe. Living things are beyond him, though he can raise mindless constructs that follow orders, much like the golems Simon Gollini calls up with Monster Summon.

He aims it at himself as well, laying down a full bodysuit that alters his build, his skin and hair color, and his clothing. The surroundings are fair game too, letting him strike at range, open pitfalls, raise pillars, and grow hidden doors out of walls and ceilings. Anything he stays in contact with remains his to revise, so damage to his creations can be undone as fast as it is inflicted.

Beneath the spectacle it is a plain ability, and an exploitable one. Everything it makes can be broken or dodged, and the kinetic shockwaves come from transmuted matter rather than his own muscle, making them an imitation of All Might's strength instead of the real article. The forest inside his fortress is artificial because he cannot make life, and his All Might body is a suit rather than a transformation; it tore under punishment and exposed the far frailer man underneath, which is why he preferred to keep opponents at a distance. Knock him unconscious and the whole edifice fails. Deku, Dynamight, and Shoto worked this out and dismantled his creations to beat him.

Valdo Gollini is the sole wielder. Following All Might's rematch with All For One at Kamino, he used the Quirk to copy the Symbol of Peace's younger appearance down to the facial structure, hairstyle, and frame, and presented himself to the public as Dark Might. Gold coins became his working catalyst: he built his own debut out of them, producing live-feed camera drones, lighting equipment, and a pillar of stone to raise himself above the crowd. In combat, coins and the metal from his rings become a glowing orange kinetic substance he hurls at tremendous speed and molds into discs, fists, spears, and shields. His first public display ended a fight with the Jailbreaker Ginji Kurau in one blow, a glowing fist that punched through the man's modified Mad Gluttony and hit hard enough to obliterate the bridge he crashed into.

Forcing Anna Scervino to feed him her Overmodification changed the scale entirely. He converted the Gollini airship and a whole sector of Japan into the Symbol of Paradise, a flying fortress holding fake jungles, snowy mountains, and a town center. As it assembled, the Quirk swelled into a vast wall of light on the move, pulling in everything it met, shrugging off the Heaven-Piercing Ice Wall that Shoto threw up, and sweeping up the students and civilians below. No longer needing his hands, he reshaped the fortress at will and mended it faster than Endeavor's Prominence Burn could break it, until Mt. Lady held a crack open for the Heroes. He also learned to delay the effect through his coins, planting them as energy spears to sprout stone pillars at a distance, and shrugged off point-blank rounds fired by Giulio Gandini's prosthetic handgun, transmuting the coins he carried into shields. Deku observed that such versatility made it look like several Quirks when only one was ever in play.

His named moves point to Italy rather than the American states and cities behind One For All's, a likely nod to the mafia origins of the Gollini Family. Bologna Smash drills a glowing fist into a target and twists on impact to send them spinning away, while Torino Smash turns the punch itself into a projectile. A second dose of Overmodification sharpened his imitation into something faster and deadlier, able to churn the earth like sand into a rockslide and to reproduce techniques All Might had used years earlier against Wolfram and All For One. When the boost overloaded, the suit and his surroundings fused him into a towering monster, and whether the Quirk reverted afterward is not recorded.