The purpose of the Iris Four system was to transmit magical signals through the blade and into the Heart of Shardmoon Castle causing it to crash-land in the Prismatic Vortex. The Iris system would then to use the necrotic space-time manipulation capabilities of the Castle to spread corruption throughout the Forlorn Rise while scying out and recording the results.
However, what actually transpired was far more Interesting. The two magical artifacts fused in a more fundamental way than was originally anticipated, and the Iris Four system began not only to gather information from the web of necrotic corruption, but to actually use it as an extension of the Heart of Shardmoon Castle to increase the effectiveness of this information gathering.
The spreading corruption became eventually metamorphosed into something of an arcane neural network, and before long, Iris Four became self aware. The blade had, over time, made itself into an intelligent magic weapon.
Iris Four was the true cause of the endless zombie attacks on the Shadegrasp Outpost. Re-directing the powers of the castle, Iris created and endlessly reviving army of the undead that gradually learned and improved its’ battle plans.
However, before the Outpost could be overrun, the party arrived at the Shardmoon Castle and soon uncovered Iris Four as the source of the evils plaguing the land.
Both before and after going rampant, Iris Four was in contact via some sort of remote signal with Raziela the Shroud. Apparently, Iris was aware of operations by someone in their leadership on the Timescarred Dial. Her intention to crash-land the castle on that island was most likely part of some scheme to free herself from any obligations to the Spiral Eclipse.
Once the party discovered the secret portal into the core of the castle, they attempted to negotiate a means by which to peacefully remove Iris Four, but eventually combat ensued. In the end, the party split the Iridescent Blade from the Heart of Shardmoon Castle, rendering Iris Four inert.
However, a crystal at the hilt of the Iridescent Blade was recovered by Raziela the Shroud. Apparently, this jewel contained a recording for the mission data from the Iridescent Blade, and since the Iris Four’s sentience had been born from that, her ‘personality’ and ‘memories’ were also recorded within. This allowed Raziela to use this to create IRIS 42.
Dialogue Theme: Halo 2 – Ancient Machine
Battle Theme: BlazBlue – Awakening the Chaos
Cornered Battle Theme: Touhou 6 Embodiment of Scarlet Devil – U.N. Owen was her?: Cool&Create Remix
Iris was originally intended to be even more of an homage to Marathon, with various messages written in the style of the Marathon terminals appearing on the network of scrying orbs located throughout the castle. Only two of these messages made it in the final adventure because I realized that I couldn’t anticipate what the party would do and I couldn’t type fast enough to improvise them.
It was actually a coincidence that coming up with a short code name for the Iridescent Blade also yielded a girl’s name. Another character was actually slated to be named Iris but this was changed because it fit so well here.