Complex sentence: As Jack heads toward Negi, Kotaro attacks Jack with every thing he has without holding anything back, but since Jacks speciality is takeing out magical beast Kotaro was devasted by Jack's fierce attacks and unfortunately only could buy Negi 38 seconds.
Split into simpler sentences: As Jack heads toward Negi, Kotaro attacks Jack with every thing he has without holding anything back. Since Jacks speciality is takeing out magical beast Kotaro was devasted by Jack's fierce attacks and unfortunately only could buy Negi 38 seconds.