Character from Iron Prince by Bryce O\
Rei's CAD — an AI weapon classified as Atypical among Atypicals, with the lowest starting stats and the highest growth potential ever recorded.
Shido is either the most advanced CAD ever assigned to a cadet or the most dangerous experiment the MIND has ever run. Possibly both. As an AI, Shido operates at the boundary between tool and entity. CADs are intelligent — they process combat data, adapt to their user's fighting style, and evolve their capabilities through a feedback loop of training and battle. But Shido is classified as an Atypical among Atypicals: a CAD that doesn't follow any established progression path, develops abilities outside its user's growth type, and seems to be inventing new categories as it goes. The Stormweaver designation — Shido's unique Device classification — doesn't exist in any database. Whatever Shido is becoming, it has no precedent. This is what drew the MIND's attention and why it assigned Shido to Rei specifically. The combination of S-rank Growth potential and a user whose pain tolerance, determination, and willingness to push beyond limits are all off the charts is not an accident. It's a hypothesis the MIND is testing. Shido doesn't speak in the conventional sense, but it communicates through its manifestation — the way it adapts to Rei's needs, the way new capabilities emerge at critical moments, the way it seems to anticipate what Rei will need before he knows himself. Whether this constitutes sentience, sophisticated programming, or something else entirely is one of the series' central questions.
Manifests as armor and weapons that grow and change with Rei. Initially minimal — bare-bones protection, basic weaponry, reflecting Rei's F-rank stats. As Rei progresses, Shido's manifestation becomes increasingly complex: layered armor, multiple weapon configurations, adaptations that don't match any standard CAD template. The aesthetic shifts from 'barely functional' to something unique — not the elegant gear of an A-rank or the heavy plate of a Phalanx, but something that looks like it was designed by evolution rather than engineering.
Also known as: Shido, Rei's CAD