I C O

BK UNIT 01 - ALPHA CLASS: TYPE: FULL/TYPE: NULL/'Silvally'

The first sucessful synthetic lifeform created in Ultramegaopolis, Unit 01 ended up looking a bit different from it's other two counterparts, being oddly colored and very large. This beast is a chimera composed of dna from every type of pokemon. The intention was to create a creature which could adapt to any situation by retrieving the Memories of the energy they were created from through a system known as RKS. However, it went berserk on the first test run and had to be restrained with the Nullifying Helm Limiter along with it's other two counterparts. Ultramegaopolis still wanted a use for these powerful creatures even if not as they fully intended, thus implicated modifications to the Null Helm Limiter left it suppressed with little free will of it's own, simply carrying out orders and murdering entire swaths of Ultra Beasts for it's 'masters'

Up until an unfortunate (or maybe fortunate?) fall leaves it's routing transmitter damaged thus and freed from the electromagnetic suppression. A small creature helps it traverse the lands, and eventually the limiter broke down, allowing The beast to fully access it's RKS system at long last.
The Small creature is the one that gave it it's current name, ICO.