Like the GTM Piranha, the Infyrno is an anti-fighter weapon carried by bombers to clear a path through defenders as they close with their primary objective. The Infyro is a much different device than the Piranha however. It is, again, a manually detonated dumbire missile. But intead of using seeking submunitions, it depends solely on high-energy explosives released within a very tight detonation pattern. It does enormously higher damage, but to a small area.
The missile moves fast and has a fair range, making it safer to deploy. But ultimately this is a very difficult weapon to use in its intended role since one must gauge by eye the necessary lead factor on its unguided path. Enemy fighters also have the annoying habit of seeing the massive chunk of ordnance come sailing their way, and break formation evade it. When it works, it works amazingly well, and entire wings go out with a single brilliant detonation; but it doesn't often work.
However the Infyrno is not entirely useless, since it can dish up absolutely catastrophic damage to light warships, freighters, transports, etc. Against these targets, the Infyrno can be considered a sort of quick-loading, dumbire antiship torpedo. Be cautious however, not to release too near the target, since you will almost certainly be vaporized by your own weapon if you're caught in the blast radius.