He was legitimately hoping for an answer to that. Oh well.

Eidolon switches from stationary in the air to matching the massive Neuroi in speed, seemingly not bothering to accelerate in between. He stays away from any part of it that looks like a weapon, but flies right into a few lucky blasts from other ones. It barely harms him, feels like an impact knocking him slightly off-course. But he's down to two useful abilities at the moment.

An invisible beam drills toward the nearest large Neuroi that Eidolon and the giant are racing toward. No time to guess and aim for the core, just firing to get it out of the way.

The Neuroi beams aren't lasers, they don't travel at the speed of light. Nonetheless, some combination of still being damn fast and leading the target and sheer volume of fire means that more and more small blows and a few large ones start landing on him.

The large Neuroi attempts a dodge, fails, and goes flying with a good third of its body dissolving into glowing white particulate. It starts regenerating immediately.

The massive Neuroi is apparently not very maneuverable- it streams straight past him, firing as it goes, and disappears into cloud cover.

The blows are more inconvenient than anything else, at least until they switch up what weapons they're using. But they are very good at being inconvenient.

Eidolon races after the massive one, spiraling to avoid fire and telekinetically clearing up the cloud in front of him. He leaves a sonic boom, even if it didn't; there's nothing here he doesn't want damaged. After catching up, he starts blasting away at it, this time trying to find the core.

The core is not in evidence after the first few blasts. Or the next twenty. It'll run out of body to hide the core in soon, though. Suddenly about half of the beams stop being red. The new attacks are white, purple, green, even black. These have effects varying from 'extreme cold' to 'space-warping' to 'gamma radiation'.

At the same time a few of the smaller Neuroi seem to teleport into his path and explode into a tangle of black fibers. If he doesn't stop in time to avoid them, they explode again into smaller fibers that are also extremely sticky. And corrosive.

Cold, not a problem; radiation, not an immediate problem; space-warping, confusing. His current defense is pretty comprehensive. But he's still ignoring the smaller Neuroi, and doesn't have time to handle the entire net. It slows him down and his armor corrodes. Some of it hurts.

His third power speeds up and finishes charging. A kind of clairvoyance, to finds the points to attack and reverse-engineer the results for more general information. Eidolon only needs it for that first bit. He spends a valuable few seconds concentrating fire at where he now thinks the giant Neuroi's core is, then reluctantly turns to deal with the smaller ones.

The giant Neuroi's core - a red vaguely sphere like polygon the size of a car - seems to have something like Endbringer toughness going on. His first few attacks leave a visible crack. The giant stops regenerating and runs for the center of the storm as fast as it possibly can, but he can destroy it completely before it can manage to escape. The giant explodes into a shower of glowing white dust.

The large Neuroi have picked up on how the space-warping is confusing him and are using it liberally to make his attacks miss, create space between him and his target, and bring Neuroi ready to attack into good positions. The clairvoyance can mostly get through this hindrance, with some effort.

A few of the small Neuroi have blade-arms, and one of these, space-warped adjacent to him, stabs him in the leg with something that partially negates his invulnerability. Another Neuroi is spitting fire in every direction. If his clarivoyancepower can tell why, it's to deprive the area of oxygen and suffocate him.

The clairvoyance may be able to get through, but knowing where the cores are does little if he can't hit them. He doesn't scream, when the blade pierces his leg, at least not audibly.

It's working. He's fighting for his life, unconcerned with allies or collateral damage, against opponents that can challenge him even if he doesn't hold back. He feels closer to his old power level than ever before.
Eidolon drops from the sky, his combination flight and weapon power replacing itself in seconds rather than minutes. Painful seconds, as he's mostly defenseless against anything that can get past his durability, but then he's back up and smashing at the nearest Neuroi in a sphere around him, pulling each one in every direction except closer. And then he starts replacing the durability with another, one with a different set of weaknesses and a healing component.

Hundreds of little Neuroi die, shells torn to shreds and cores shattered. Some medium-zide and one large Neuroi falls to this attack as well. Though more reinforcements are arriving steadily, he's thinning them out.

The storm has been getting stronger and stronger over the last two minutes. Now, lightning starts striking Eidolon whenever no Neuroi are near enough to also be fried by it. A storm this big contains more energy than several weapons of mass destruction, and this lightning seems to be sending a sizable piece of a percentage point of it at him. The air around Eidolon glows with electrical plasma, and the air nearest to him is no longer breathable - all the oxygen molecules have been split into free atoms.

Meanwhile, four of the remaining large Neuroi are reshaping themselves, though what exactly they're aiming for with the change isn't clear yet.

Eidolon did change out his defensive power for exactly that reason. But apparently he's still incompletely immune to that. Rather than remove the barb on the spot, he applies gravity. A sufficiently strong jerk against one part of the tentacle with an equally sudden grip pulling the other way, only a fraction of an inch apart, ought to snap more or less anything in two. He can remove it later.

If he were only fighting to win, he could leave and clean up the swarm of smaller targets first. He's also fighting to fight, and this is clearly the target. Eidolon has a lot of force to play with. The nearest large Neuroi gets squished inward from every direction except front and back, where the opposite happens. For good measure, he adds in some literal spaghettification. See how well it can defend itself while time-dilated.

The Neuroi that is suffering his wrath explodes. The other three deploy some kind of energy shield that... Looks kind of familiar.

It's Copycat's shield. Well, technically, a Witch shield since they can all do it. Where did the Neuroi learn that? At any rate, his gravity power is significantly less effective against anything behind them.

The Neuroi try cold again. The air around him liquefies.

Liquid air is a problem. He stops breathing at all; he'd rather have that air's return to normal take place outside his lungs.

He drops the clairvoyance power, looking for something to make him completely self-contained and resistant to harm. A breaker power, that would do. He turns into what looks to be diamond, and feels it growing even more durable. As soon as it seems powered up enough to protect him from what he's up against, he drops the other defense. Gravity for flight and wide-area destruction of the Neuroi that aren't using Witch shields, ability to hopefully take any hits he can't dodge, and a better weapon for the three main targets as soon as it's ready.

The Neuroi start their psychic scream again, but that diamond-breaker power seems to be blocking most of it. The next time one of those annoying invulnurability-piercing blades hits him, it bounces.

The little Neuroi continue to die in droves. A few more big ones have shifted to this new configuration. One of them looks like a bit like a giant umbrella/octopus/jellyfish, it attempts to entangle Eidolon and smash him into the ground. Oh, and they're all still firing beams of various sorts at him of course.

The big ones that aren't behind the Witch shields can get unfair quantities of gravity, just like the last one.

For those that are, his latest weapon is ready faster than anything of this scale has been in years. He always knew one good fight, a real fight, would go better. Here he doesn't have to worry about the world collapsing if he dies; his allies would have time to prepare for the next Endbringer. And he isn't playing a role as Eidolon the all-powerful hero, he's just fighting. His powers are working as well as he can remember, and he's even daring to hope it might be permanent.

A tennis-court-sized area appears and sweeps across the sky. Things it intersects get deleted. Matter, energy, doesn't matter. Magic, maybe, but he'd be surprised. Air rushes in to fill the newly created voids. The one with the tentacles can be the first to go, then those other three...

The Neuroi have no defense against this. They scatter and die and flee.

And then a suicidally teleported Neuroi core is occupying the same space as a third of Eidolon's upper chest. This does not end well for either being. Eidolon is still alive long enough to register the injury, then they do the same with a large section of his brain.

They didn't want to kill him, not really. He was extremely powerful, a being capable of actually threatening a grand core. But he was getting that strength from somewhere else. That is not the point of fighting humans.

Eidolon wouldn't have been able to save the world if he hadn't tried this. If he wasn't strong enough and was getting weaker, this is no great loss.

But he was, technically speaking, right. One real fight, if it was a good enough fight, could get his powers back for the rest of his life.

The Neuroi take a few minutes to analyze the fight. It's good data, first-hand information on some of the nastiest things this new variety of Power can do.

Then they decide that, with this much power floating around out there, it's time to stop holding back. Fresh Neuroi from the core of the hurricane stream out in all directions, launching assaults on the Witches ringing this section of the world in all directions. There are just enough serious attacks to keep all the dedicated military Witches busy, and plenty of smaller threats to force the non-military humans to join the fight.

By now the Neuroi called/numbered Seventeen, the ship-sized gigantic core in the center of the hurricane, has finished summarizing everything to the other greater Neuroi.

The Twelve decide to invade the Earth that Eidolon came from. Hopping dimensions is tricky to figure out, but they had a good view of someone doing it just now with Eidolon, and a couple months ago when a random anomaly pulled a drone through the wall of universes. In about eight hours, they've managed a configuration that allows a drone to become a Doorway.

Eleven joins Seventeen on Earth Gimel. FTL is expensive, but things are moving quickly. Proper oversight of the increased stakes is important. It makes another humanoid Neuroi, which spears Eidolon's body on an arm-blade and flies through to wherever-Eidolon-gated-from.

In approximately no time at all, it's faced by two of wherever-Eidolon-gated-from's other heroes. With an audience of more.

"Why are you here?" Alexandria asks it.

It throws Eidolon at Alexandria and screechily lies, Revenge.

Then it starts blasting. The gate moves high into the air, enlarges, and the swarm pours through.

Revenge. Alexandria doesn't believe that for a second; they'd be striking at Earth Gimel or they would have attacked here after Bet started arming them. But that's hardly the point right now.

Heroes and even villains join the impromptu S-class battle, blasting the Neuroi with whatever they've got.

Well, they are also striking at Earth Gimel, but that's beside the point that this city is being blown up piece by piece.

The Neuroi keep pouring through. But it's going to be a short S-class battle unless the heroes pursue- When a huge Neuroi passes through the gate, they retreat in good order, sacrificing themselves to protect it when necessary as the whole swarm flies north. (Still blasting at anything close enough to blast because why not.)

The giant Neuroi is pretty tough. It only bothers to dodge the most serious attacks. A storm starts to gather as it moves, and pretty soon it's repeating the tricks it used against Eidolon. Air-liquefying cold, lightning, various exotic beams, invulnurability-piercing blades.

Ultimately, though it's a fierce fight, this looks a battle the heroes can win.

It's also a diversion. The gate moves to the outskirts of the city and an even larger Neuroi comes through once the heavy hitters have left the area. It speeds south as fast as it possibly can.

And that's just unfair.

Reinforcements are arriving from around the world, but few can keep up with the new Neuroi and even fewer can hope to do anything to it.