The Solacris was a technological solution for a caretaker species and was designed by the Asgard. However, it spectacularly backfired against them and led to it crippling their race as well as created the plague that killed the Ancients that did not ascend. The creation of Solacris was the reason for the dissolution of the Alliance of Four Great Races. (Stargate Worlds)
The Solacris was intended to be a key player in Stargate Worlds in the post-Ra content.