KO One: The Sign-In System Gives Me an Invincible Combat Rating

Gu Feng accidentally transmigrates to the superpowered world of KO One, bringing along a sign-in upgrade System. All he has to do is sign in each day to increase his combat power index. 【Congratulations, Host. Today's sign-in is successful. You've been awarded 100 combat power points. Keep it up!】 【Congratulations, Host. You've triggered a hidden mission and earned a reward: Wang Dadong's ability to grow stronger against stronger opponents.】 【Congratulations, Host. You've signed in for 300 consecutive days and earned a reward: The Sword Within a Sword, a weapon forged by the Mother of Weapons, Dao Gui.】 【...】 With his powerful abilities, Gu Feng joins the battle between the superpowered factions. Together with Wang Dadong, Xia Tian, and the Alliance Leader, he takes on the Demon Lord Diabolo. Xia Yu and Xia Tian are dead? I'll travel through time and save them! I won't let you die. All of you, stay alive! The Flame Messenger wants to reset the timeline? Get back to your Time Administration Bureau.