Lights
For Leonardo, it was the lack of light that provided the most security.
In total darkness his extraordinary focus gave him a complete advantage over his adversaries. Cloaked in the invisibility provided by the protecting blackness, Leo swept in and through, unerringly laying waste to those who so unwisely chose to challenge him.
The dark helped him to train his brothers as well. When they sometimes chose to defy his leadership, or test his patience, Leonardo would turn out the lights.
Better than most in the darkness, the three younger turtles were still overly dependent on their eyes. It was in this venue that Leonardo became 'Master' and his brothers were reduced to acknowledging their oldest brother's dominion.
With the lights out Leo could hide his secret fears as well. The insecurities that sometimes plagued him were not visible to anyone, including himself. It gave him a much needed respite from the demands of leadership he so willingly shouldered.
Leonardo owned the darkness and to him, light was the enemy.
For Donatello, the light from his computers represented his intellect.
The world in which they lived was barren, harsh, filthy, cold, and damp. Don's mind provided his small family with the comforts of a real home. The used and discarded computers that he rebuilt gave them more; it allowed them to reach out into the world without having to unnecessarily expose themselves to its dangers.
Their security was enhanced by the technology Donatello was able to provide, their mobility was trebled by the motored vehicles he built. Life's simple pleasures, which they had only dreamt of as youths, became attainable through Don's vast knowledge.
In a fight, it was Don's genius that pulled them through more often than not. It was his ability with computers that allowed the brothers access into their enemies domains. It was his sharp mind that pulled them back out again.
Donatello soared within the limitless reaches of the lights from his computer screens.
For Raphael, it was the lights of New York City that offered him comfort.
Out in the open air, free from the confining walls that so often threatened to suffocate him, Raph found room to breathe. He would gravitate towards the brightest lights that he could find and spend his time enjoying the simple pleasure of watching life ebb and flow in the streets beneath his perch high above them.
Crime was something he did not abide; it ate away the mellow peace of his surroundings and offended his morality. To crush it quickly and restore balance to his beloved city was his foremost goal. Like a vengeful wrath his justice was meted out swiftly and woe unto those who begged for his mercy. Raph had none to offer vermin; in his mind they did not deserve it.
The rewards for his vigilante justice were few but he didn't need them. All Raph wanted from life was the chance to live it and find some small measure of enjoyment from doing so.
He knew that his brothers understood him, even if he sometimes swore that they did not. When he needed them, they were always there and that itself was testament to their bond.
Raphael needed the city lights and his family, nothing more.
Michelangelo loved the spotlight and the chance to shine.
Joyful, energetic, and effervescent, Mikey's inner being was warmed and fed whenever he was the center of attention. He loved those rare moments when everyone's focus was entirely on him. Mikey lived for the chance to dance inside the brightest circle of light that he could find.
The sound of thunderous applause rode his daydreams; the acclaim of those he looked up to offered him warmth. Whether on the field of battle, in the middle of the Battle Nexus, wearing a cape as the Turtle Titan, or simply delivering a crushing video game loss to a brother, Mikey basked in the glow of his time in the limelight.
As much as he enjoyed that light, its shine was bittersweet. Too short in duration and too far in between, Mikey knew he was destined to chase the rare chances to stand under it and bask. The life that had been offered him did not come with the opportunity to show how unique he was and thus to glory in well-deserved praise.
His family and friends gave him what they could, sometimes begrudgingly, often meaningfully. They knew that he was naturally gifted, amazingly so, and he could tell it pained them to see him relegated to such a lonely, hidden existence.
Michelangelo gloried in those infrequent moments as the center of attention.
Master Splinter found inner peace and tranquility surrounded by candle light.
His life forever changed by the happenstance of his proximity to four tiny turtles and a broken canister of ooze, Splinter answered a call to duty he did not even realize that he'd heard. His Master spoke to him from beyond the grave to raise those mutated turtles as his sons and thus to extend the legacy of their clan.
The circle of life allowed a lowly rat to become much more; a father, a scholar, a friend, a champion, a teacher, and a Master. Hamato was the family name that he was destined to carry forward and in his wisdom he determined to carry it with both pride and humility.
Losing Master Yoshi and Tang Shen seemed to strip him of any chance at love, but the four turtles who became his children gave him all he could ever want. His pride in them was without limits, his oath to protect them would stretch to the giving of his life if ever the need were to arise. They were his world and his life; they provided him with a reason to exist.
Master Splinter mastered fire when he lit his candles, and the fire likewise mastered him.
All five agreed that the rarest light for them was provided by the sun.
They did not get to see it nearly enough and when the opportunities arose, they allowed it to drench them in its warmth. Lying on the grass at Casey's farm, the brothers basked together under its brilliance, behaving as normal turtles would. Master Splinter enjoyed the brightness of daylight from beneath a cool canopy of trees, eyes filled with merriment as he watched his sons regress to a more youthful time in their existence.
One light above all others was more precious and more desired by each of the turtles.
This was the light they saw in each other's eyes. So bright, so alive and full of love; this was the light they would cling to in their darkest hours and this was the light that kept them fighting when the odds were at their worst.
The warmth of a brother's touch, the spontaneity of a brother's passion, the physical joy of a brother's caress all were things that lit the fire behind their eyes. It filled their hearts with the kind of emotion that made them stronger as a whole and completely unbreakable as a family.
The other lights they could live without, this one they could not. The bond provided by this one light gave them a reason to stay alive, it pulled them forward when they were in pain, and it provided a kind of joy that no possession ever could.
The light of their love shone brighter than a hundred suns and it was the only one they really needed.