EM-1

In his previous life, John was an otaku. So of course he had watched anime and knew that Electromagnetic Weapons were one of the most powerful arsenals used by the protagonist. He had also read the theory behind it.

To make it, it's very easy. You just need two parallel platforms. Both platforms must be coiled. When electricity passes through the coil then one must be clockwise and the other must be anticlockwise. Finally put the projectile in the center which would use the electromagnetic field to accelerate and shoot out of it.

After knowing the principal behind it. He immediately began to work and it didn't take him much time. Within just a few minutes, he completed the structure. After that, he put the projectile and with a flash, it disappeared into the water.

The current model was small in size and was made from bronze-tier materials.