Maybe a Fake Gintama - Chapter Master of Heiwa, Master of Kouan, and the Man Who Will Be Bald in the Future

In a world teeming with Titans, Colossals, Gigantic Monsters and Kaiju's, Erian who reincarnated makes his living collecting scraps of low-grade Defective Genetic Serum, realised he transmigrated along with his system.

Follow Erian as he grows to become the strongest Disaster Grade Titan with the help of his Titan System!

Vincent Strider was a gun for hire who made a living by killing whoever it was his clients wanted dead. But during one mission, he died in a fierce gunfight. However, death was not the end for him. Vincent found himself reincarnated in another world, facing a floating interface that flickered before his eyes.[Synchronizing Host!][Military System initializing.]Vincent found out that in this system he received, he can summon soldiers, tanks, aircrafts, and even warships! This is going to be exhilarating.

When a national athlete of China laughs at being able to win a gold medal in video gaming, what a pro-gamer like yourself ought to do is take your size-42 shoe and measure it against his pretty face!

Tong, a sinner who was suffering endless torment in hell because of his mistake he had done in his previous life, was giving other chance to redeem himself by the devil.