Arch-guns are guns only used in Archwing combat. Unlike traditional Warframe weapons, Arch-guns have no separate ammo reserve and magazine, instead having a regenerating magazine whose contents replenish to full when the weapon is not firing. The delay from ceasefire to replenishment and the speed of ammo regeneration varies between different Arch-gun models. Because they have no ammo reserves, Arch-guns essentially have unlimited ammunition, and thus do not require replenishment from ammo pickups.
There is a wide variety of arch-guns, with different trigger types, effective ranges, and projectiles. However, they all use the same Arch-gun mods. As a brief rundown of the more special types, the Fluctus, Grattler, and Velocitus have travel time; and the Corvas and Velocitus have charge fire. The remaining weapons are hitscan (Cyngas, Dual Decurion, Imperator, Phaedra at time of writing), and tend to perform like variations of certain standard guns.