Presumably developed by the Spiral Eclipse based on Iris Four. Since the Iridescent Blade was not originally intended to be sentient or combat-capable, it seems likely that the Iris Series was developed recently using the data that Raziela the Shroud took from the Iridescent Blade at Shardmoon Castle.
The Iris Series were deployed by the Spiral Eclipse as covert guards for the Meteorite base on the Banished Crescent. They were apparently brought in specifically as a counter-measure against the party.
In FanOut Gaiden, Cinderfall carried Iris Series constructs with him to serve as back-up.
A shadowy form animated by a magical knife made of synthetic Epochite. Iris Dagger units use rogue-like ambush tactics and fight with small blades of radiant or necrotic energy projected from their hands.
They also seem to be capable of a sort of creature-to-creature teleport similar to an assassin’s shadow step.
A shadowy form animated by a magical arrowhead made of synthetic Epochite. Iris Arrow units snipe from affar with radiant and necrotic energy arrows. The energy from these arrows tends to linger in the target after a successful hit.
Iris Arrow units work in pairs, since being hit with arrows of both types can have powerful, debilitating effects on the target.
Pointless Gundam/Seacats Commentary
The “Iris Dagger” name was definitely an homage to the Strike Dagger from Gundam SEED. Making them behave like rogues/knife fighters followed from the name.
I can’t remember at what point in the design process I realized that a being whose true form was that of a magical-looking knife was essentially the same concept as the Stakes of Purgatory from from the Seacats. In any event, I decided to yes…and this
blantant ripoff homage by giving them the energy locus radiant knives.