The space platform Helios was commissioned in response to the nuclear disaster that destroyed millions of lives (see Chaos Advent). It's purpose was to serve as an eye in the sky allowing greater Hunter intelligence gathering as well, when the situation called for it… Precision laser strikes with it's powerful beam cannon. Though the beam cannon never saw much use.
Attention Rookies Plot spoiler
Attention Rookies Plot spoiler
However, in Attention Rookies, the Helios laser was fired by Signas as a last ditch offensive to protect the Maverick Hunter HQ when the mavericks launched an enormous fleet to take it down. The blast caught Signas in it's wave and utterly obliterated him along with a significant portion of the Maverick forces. But the laser would have ended up in significantly more loss of life had it not been for “Megaman X” who showed up and used every ounce of his power to fire a counter beam to hold the laser off for a few more brief seconds to allow more Hunters (and even mavericks) to escape. The blast killed “X” in the process.
However it was later revealed that it was not X who had died here.
The space platform is named after Helios, the Greek personification of the sun. A fitting name given that it floats high above the Earth, uses solar energy for a power source and shoots high energy waves of light and energy.