|The contents of this article have been cut.|
The subject matter of this article contains in-development information that was cut from the final version of an official and/or canonical source and appears in no other canonical source. It may also contain incomplete information since not all cut material is publicly known.
Quantum event / wildlife
The Particle Storm is an enemy cut from Half-Life 2. It only exists as sound files, although information about it can be found in the Half-Life 2 leak source code. It is unknown if it was to have come to Earth through Xen.
In the folder "sound/temp/eli" from the playable Half-Life 2 leak files, Eli Maxwell seems to be telling Gordon about an entity called the "Storm". In that speech, Eli warns Freeman to run when he sees a "flicker of green light" while being "out there", as it managed to tear off one of his legs when he made "the mistake to study it" (while the final version uses a Bullsquid instead). The "Storm" was therefore to emit a green light, somehow recalling the portals' and the Resonance Cascade's green color seen in Half-Life and its expansions.
 Behavior and skills
In the speech mentioned above, Eli also talks about how he has seen a Particle Storm tear gunboats, filled with soldiers, to bits, and believes that, contrary to some stating it is a mere "electrical disturbance", Particle Storms are somehow intelligent ("(...) but if you ask me, there's an intelligence in there, somewhere..."). He wishes the Resistance could communicate with it so that it could join their side as a "powerful ally". This indicates that it is not a Combine creation, but rather a wild "creature", sentient and powerful enough to destroy gunboats, kill living beings and simply cut off a leg, as mentioned above.
Another related folder from the playable Half-Life 2 leak files named "particle_storm" can be found in the "sound/npc" folder. It contains four sounds the Particle Storm was to emit, associated with different moves: "form", "dissipate", "hover", and "lightning". It was therefore to probably form out of nowhere in front of the player, hover above the ground and emit lightning flashes.
 See also
|Black Mesa Incident · Particle Storm · Portal Storm · Resonance Cascade · Superportal · Teleportation · Warpball|