The Inciters are an alien techno-organic collective being, capable of forcibly assimilating organic life and making them part of their collective in order to use as fuel. Although long spoken of as part of Shi'ar folklore, their actual existence was not confirmed until recently, when they emerged from a rift in space, destroying the planet Zenn-La and absorbing its people.
The Inciters went on to manipulate the powers of the human hero Binary, tricking her into believing she was stabilizing a star on the verge of going supernova. In reality, they had arranged things so that her powers would actually accelerate the star's destruction, causing it to supernova at the same time as two other stars they had affected, setting off a chain reaction that would have destroyed much of the Andromeda and Milky Way galaxies, devastating Earth, Chandilar and Hala alongside countless other worlds. Whether this devastation was intended to further empower the Inciters or was simply a means of destroying any threats to them is unclear.
When their plan was uncovered by the X-Man Beast, the Silver Surfer, and Rogue flew to the Inciter's location and engaged them in battle. Rogue was briefly assimilated into their collective, but was freed by the Silver Surfer, who used the Power Cosmic to obliterate the Inciters and bring an end to the suffering of the billions they had enslaved.
Following these events, the Shi'ar ruler Lilandra chose not to make public any information about the Inciters, fearing that revealing that the Inciters actually existed would cause turmoil and unrest throughout Shi'ar society.