Cavalier -

Originally an ordinary bike, Cavalier came to be when Issei had tossed a fireball at his opponent only to miss because the enemy had dodged. Doused in his flames, the bike was transformed into something more deadly. When not used as a means if transport, Cavalier can turn into a twin pair of chainsaws that deal heavy damage to all who are hit.

The Hell Cycle -

In direct contrast to the Cavalier, the Hell Cycle can't transform into a duel chainsaws. The bike shares many of its abilities with the cars instead. However, Issei can't teleport nor can he phase through the vehicle but it like all the over vehicles can self drive themselves to him should he desire it. In addition each and everyone of his vehicles hold some degree of sentience. Issei gains the bike in Tokyo city.

The Hell Charger -

Unlike Cavalier, The Hell Charger was intentionally infused with Issei's flames but instead of being transformed by the the fire the car largely remained the same save for the flames that now spewed from both its engine and wheels. The car itself also gains somewhat of a symbiotic bond with Issei allowing it to appear when he needs it and alter itself to fit the proper terrain. It's trunk also connects to a small space in the Dimensional Gap that not even Ophis knew about and it is where Issei had been sending all his items and weapons. Also Issei also gains the ability to teleport into the car something he discovered when he was separated from Ravel and Kunou in Tokyo during which he also learned he could phase through the car due to being almost being run over by the girls.

The Void Stalker -

A Pure black Chevy Camaro that Issei gained while on Tokyo as he tried to get back to Kuoh town. Infused with his flames, the car can perform many of the same things that the Hell Charger can do. Perhaps his instincts as a dragon have started to set in otherwise why would he start collecting these cars.

The Ember Rider -

Issei has really taken to naming whatever he owns with this more modern version of the Camaro. Similar to the over cars Issei has gained this one won't be any different save for the fact that it can fly due to all the technology stuffed into it. In addition, it's also a convertible.

The Inferno Chaser -

People have started to realise that Issei must really like Camaro's. Never the less, an oldy but a goody Issei has stated that he was a big car fan but just didn't show it. It shares many of its abilities with its predecessors however it can also retrofit itself on the fly.

The Dark Viper -

A customer military grade jeep that Issei acquires after his group stumbled across an abandoned military camp. Infused with his power, the jeep has similar abilities to the rest aside from the ability to fly like the Ember Rider but it is chocked full of tech and Issei is constantly improving the vehicle whether it be through his flames or engineering skills.

The Summit Seeker -

Issei created this vehicle to act as a major improvement to the Dark Viper. Issei created this to be the ultimate All-terrain vehicle that's almost indestructible while slower it does have big space in the back to allow him to enter the Dimensional Gap without having to enter the boot of his other cars but it's also choked full of highly advanced tech with much help from Offensive Bias.
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Note - due to Issei being part dragon he also has their habit of collecting and hoarding things at first it wasn't so bad but now that he's absorbed more of Ddraig's powers whilst he was in a coma the habit was somehow made worse. Of course this lead to him taking engineering classes privately with Azazel. Once the faction leaders sealed themselves in with the beast of 666, Issei had taken to quietly taking engineering lessons whenever he had the chance. His engineering skills will come in quite useful in the future especially if applied to blacksmithing, another useful skill that Issei will improve upon as time goes on.