Naruto: Fusion System

Transmigrated into the world of Naruto, he obtained a Fusion System. By fusing with a simple tree branch, he unexpectedly gained the ability of photosynthesis. By absorbing sunlight, he could not only recover stamina, chakra, and heal injuries, but also continuously grow stronger. It was insanely overpowered. “Youth needs passion! Rin, let’s go train!” Might Guy shouted energetically. “Not going. I’m going to sunbathe,” Uzumaki Rin replied, shaking his head. “Let’s hurry and carry out the mission,” said Kakashi Hatake. “No. Nighttime isn’t my domain. We’ll go tomorrow during the day.” Rin looked up at the moonlight and shook his head again. Fusing with a tree branch was nothing—fusing with chakra-conductive metal was the real deal. — Description from novelcodex.org