7 Deadly Sins

History
7 Deadly Sins are fighting styles/techniques developed by Doyle during his stay at Signal Academy. It maximizes the capabilities of his weapons.

Stances
Belphegor (Sloth) - This fighting style focuses on long range attacks only. Doyle alternatively uses his guns, when one runs out of ammo he puts it back in the holster and Uses Mammon for it to reload. Doyle is also capable of using the guns for propulsion, allowing him to fly and move at great speeds. He also uses the guns for evasive maneuvers. (Used only for weak types and for traveling long distances when he's too lazy to walk.)

Leviathan (Envy) - This is a fighting style which focuses on landing strong blows and kicks. In this stance, He moves at a faster pace, often catching the opponent off guard. As opposed to his normal long-ranged tactics, Doyle fights in a more close range way, resulting in more damage with his weapons and physical attacks. This fighting style is usually used for hand-to-hand combat but Doyle uses his guns to deal more damage to his enemies.

Lucifer (Pride) -  This fighting styles is only used Sadist Doyle, he uses the recoil  when it guns are fired in blade form to spin at an incredible speed and he cuts anything the blades touches in the path.

Techniques
Asmodeus (Lust) - Used to know the potentials of his opponents by just observing them during a fight.

Beelzebub (Gluttony) - The ability to absorb an opponent's energy attack through the guns, then reverses the attack's original course by firing the same attack at full force, making it much more difficult for the opponent to dodge.

Satan (Wrath) - This technique uses the long sword form. It is an "ultimate killing technique" that releases all of the ammo's charged energy from the tip of the blade once the sword is swung. While the result is what looks like a large beam of light, only the tip of the attack, which is a wave of light that can mow through the surface of the Earth, is capable of doing damage, as the beam is the result of the "dislocation" of everything the attack destroys in its path. Even if it is dodged, those in close proximity can still be temporarily distracted by its intensity.

Note
Mammon is not included here because it's Doyle Semblance