Bear Infestation: I Am Dragon Ya, I Am Invincible

Ryugen is an ordinary middle school student. On the day after the college entrance examination, when he went to pick up the Kamen Rider Ryuga cassette and belt he bought online, he was transported to the world of Ryuki by a 100-ton king and became Kamen Rider Ryuga. In the mirror world knight war, he sang all the way, defeated all the knights, obtained the survival card, unlocked the survival dragon tooth and defeated Odin. After defeating Odin, as if fate played a trick on him, he traveled through time again and came to a world infested by bears. After coming to the world where bears are infested, Long Xuan found that something was wrong with this world, because there was also a knight war here. Not only that, but even some villains from the special series were here. However, the existence of the villain did not affect his life in Gou Xiong Ridge. When he should be messed up, he would be messed up, and when he should lie down, he would lie down. Until the emergence of the later system, he was forced to embark on the peaceful road of safeguarding justice. Long Xuan: I finally got through the knight war, but I can't rest. I'm playing tricks on you, fuck you. (Single heroine + system or not + decisiveness in killing + invincibility. Note: The system is useless. It will only occasionally send equipment to the protagonist. When to send it is decided by the system)