#funfact for the tag readers: shining a flashlight on his physical form hurts him

[sad-leon]

Welcome to the Shadow Leo au :D

It's a lotta text, but I don't know if I'll make a fic for this au. It'll probably be a lotta fics and doodles. Asks are encouraged :D

When Splinter explodes Draxum's lab, a crystal Draxum wanted to experiment that held a bunch of shadow power, dropped on Leo, fusing him into shadows. He can only appear where there is shadow, so he can't go outside alone or in really bright rooms.

He can choose whether to be visible or not in a shadow he occupies, so if he's around strangers, he stays hidden.

Because of all the light from the explosions, he hides in Donnie's shadow as Splinter leaves. He doesn't show himself to anyone outside of Donnie for a long time. It's only when they're toddlers that they speak. Leo's speaks first and scares the hell outta Donnie. His voice has a bit of an echo-reverb tone, but otherwise normal.

Donnie tries to show everyone, but eventually let's Leo explain that he's scared of meeting everyone. He grew up with Donnie, they know all about each other and their triggers and such. Leo doesn't have that familiarity with the others and he's scared of breaking down in front of them.

When Donnie brings April to the lair, Leo is excited at the prospect of meeting someone who is also an outsider. When she and Donnie hang out in the lab, Leo shows himself to her. She tries to punch him, she just bruises her knuckled on the wall. Over the years, April, Donnie, and Leo become an indestructible trio.

The fam still doesnt know about Leo when they break into Draxum's lab. Draxum immediatly notices Leo in the shadows and gathers all his mystic crystals to try and break his shadow powers. On of the crystals he hits Leo with grants him the ability to emerge from the walls, though his still looks all shadowy.

Leo still chooses to hide in Donnie's shadow, though he ventures out on his own a bit more now that he can hold swords and stuff. Leo still steals the odachi from Draxum, but his use of it is limited to only slicing, though if Donnie swings it, Leo can influence the portals if he's connected to Donnie's shadow.

[Sidenote: when the brother unlock their Ninpo, Leo unlocks his as well, granting him ability to use his portals himself. He can also do the funky teleportation thing.]

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Leo's out on his own one night when he see's Usagi hanging around the turtle fam's lair. He appears to the rabbit and surprisingly, the rabbit doesnt freak out. Usagi and Leo are quick friends. Leo tells Donnie about Usagi and convinces Donnie to meat the rabbit and eventually, Usagi becomes an honorary turtle, just like April.

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(Leo is still Casey's future sensei, but by then they had found something, a charm or a potion, that made him physical. When Casey asks about him, Donnie avoids eye contact, but everyone else is confused.)

(The key is snatched by the foot clan because Raph couldn't get to it fast enough. Leo tries to blame himself because if he wasn't so scared he could have used his portals to get it. Donnie won't let him blame himself, and neither will anyone else when they finally meet him.)

During the movie events, Leo connects to Raph's shadow when Mikey and Donnie get flung off. He makes himself physical and pushes Raph toward his brothers. He also snatches Raph's wrist comm. Raph is too panicked to consider what just happened and jumps off to catch his brothers.

He shouts for CJ to close the portal. Casey immediatly follows the command shouted by his sensei's voice before he can process it. Leo stays physical long enough to keep Kraang distracted, then ducks into the shadows.

With the whole Prison Dimension being basically one big shadow, Leo is able to stay hidden after the portal closes. He doesnt heal in the shadows, but his inuries don't worsen. It takes about a year until Leo finds his sword and portals himself home.

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Donnie, April, and Usagi are all a fucking wreck in a way no one understands, no matter how much they explain Leo and his predicament. Raph explains that he was pushed by a shadow and Donnie breaks down on the spot. Because even though Leo would never meet the fam, he'd still sacrifice himself for them.

For months, Donnie begs Casey Jr to tell him how Future Mikey opened a portal, but CJ won't say anything past explaining how it killed Future Mikey.

Donnie doesn't stop looking for any sign of Leo, but after months he has no choice but to move on. Leo's sword was put in a glass, guarded case after Donnie tried to use it to portal to Leo.

Sometimes Donnie sits in a dark corner and talks to himself.

Then one day, the alarm attached to Leo's sword goes off. Everyone thinks it's Donnie trying to portal again, but they all rush in to see a shadowy Leo injured, on the ground. Donnie breaks down on the spot, but tries to pull himself together enough to help with bandaging what they can see of Leo's wounds.

Leo wakes up to his family around him and finally lets himself meet the rest of his brothers.