Same effect here, different frequency. The aliens had different wiring. If you wanted to hurt them, you tuned for the wavelengths that forked into the nervous system and didn’t let go. Electromagnetics were the same everywhere; you just had to know the right frequency. Pain flowed into you on invisible wings.

The other aliens were running away. No, herded away.

The brown football was churning across the sky, angling its antennas toward the crowd it swept before it. He watched the hundreds of fleeing figures rush down the canyon. A rabble.

“Maybe they’re rounding these up,” Irma said at his side.

“Nope,” Aybe said beside her. “Getting them out of the way, yes. They’re after us. That was our reception committee, Quert’s people. The ones up there are running them off. I think—”

Then there was no more thinking as the brown football forked down more of the green rays. This time the enormous hollow whoosh thundered on for endless moments. They ducked. Debris blew by them. Pebbles rattled against rock, and big orange, broad-winged birds fell from the sky, squawking as they died.

They stood and watched as the dust cleared. Cliff didn’t want to acknowledge what had happened, resisting what his eyes told him, until at his elbow Quert said in its slow, sliding sibilants, “Know we share with you. They kill us.”

“Where can we go?” Terry asked in a dry croak, eyes jittery.

Cliff felt the same—dozens of Quert’s folk had died a few hundred meters away. Thin screams came from there. And the football was moving this way.

Quert, too, seemed shaken, its face a frozen stare. Slowly the alien drew its eyes away from infinity and said softly, slowly, “We share under ways. Must cross open spaces now.”

“Why is that—” Terry groped for a word, failed. “—that thing in the sky shooting at you?”

“You they seek,” Quert said simply, eyes still dazed.

“So they’re after us?” Aybe asked, eyes wide.

“We heard you come. They know also.”

Aybe eyed the living dirigible. “So they’ll come after us.”

“And we. Oppose Astronomers now.”

“Then we have to nail them,” Aybe said firmly.

Cliff saw the logic. Their pursuers knew the terrain; they didn’t. “But we have no—”

“Use their guns. Can’t be that hard.”

The cries outside diminished. They looked out carefully and saw the big balloon was dealing with their victims, slamming down shots at them. “Distracted,” Terry said. “Let’s blow a hole in them. They’re in range.”

If the enemy’s in range, so are you, Cliff thought but did not say.

*   *   *

Of course, the brown football turned and started beaming their pain gun again. The burst caught Quert while it was showing them how to aim and fire the auto-fed gun. Quert doubled up with the pain and went into thrashing jerks, head lolling back, eyes popping out as though pressure built inside its head. An awful sight.

With Terry, Cliff carried Quert into shelter. The pain gun cleared the area swiftly. Howard got a gun going and showed Terry how to manage another. They fired them intermittently as the brown football slowly made its way toward them. “Must be done killing the others,” Terry said laconically. “We got maybe ten minutes before they can do that to us.”

Cliff looked at the big lumbering thing in the sky, working its fins and—were those fans running under it? Yes, pushing the strange hybrid of life-form and engineering across the distance, maybe ten kilometers. Worse, the wind was with the thing.

They poured on the fire. The smart rounds burst into fragments as they neared the target, tearing into the wrinkled hide. Primitive weaponry, Cliff thought, and suddenly saw why. Quert’s kind were unused to warfare, he gathered. No steady gun crew discipline, a lot of strange shouting. They had not done it before, and these guns were their first real try. Battlefields, Cliff reflected, are not the best place to learn your lessons.

Abruptly came the counterfire. He saw green stabs for an instant and then the cliff wall nearby shattered. He knew this only as he shook his head, on the ground. It had slammed him down and now he saw everything through a spatter of fractured light and clapping, hollow explosions. Shock, he thought. He drew in a big lungful of air, flavored with the tang of dirt. He got to his feet and helped Irma up. Dust clouds blew away in the wind and he saw that their artillery piece was shattered where a large rock had hit it. A few meters to the side, and it would have killed them all.

“Other … other guns still work,” he croaked.

They limped to one nearby and Aybe jerked open the breech. “It’s loaded. Let’s give ’em hell.”

They got it to firing, following shouted instructions from Quert. Cliff knew he was still dazed and stood aside as Aybe and Terry aimed it. There were systems that did sighting mounted on the gun deck, pictures that homed in and locked. Quert told them again how to work it, speaking patiently and slowly from shelter. The pain gun was still going, he could tell—the Sil who darted out to help others jerked and cried with the sheeting pain.

The gun slammed out shots at the approaching target. “Aim for the underside.” Irma pointed. “There are portals there.”

Aim changed. Shots exploded into shrapnel just short of the yellow ports lining the bottom seam of the big balloon creature. They could see the impact, kilometers away.

“That’s a living thing,” Aybe said. “It’s gotta hurt.”

The creature was unused to this. It flinched when the rounds struck—long waves broke across its skin, like slow-motion impacts of a huge fist on flesh. It began to turn.

At its side, a smaller craft burst from a green pod. It was a slim airplane and fell away in graceful arcs. All the action was smooth, slow. Then their guns ran dry and a silence fell on the canyon.

“Astronomer goes,” Quert called weakly.

The huge creature hung in the air and small things began emerging from it. They crawled like spiders across the skin and covered the gaping red wounds with white layers.

“Fire some more?” Aybe asked. He had used up the ammo store.

“Don’t think we have to,” Irma said. She was getting her composure back, patting the dust from her pants and blouse, and even brushing her hair into place.

Everyone quieted down. Faces human and alien alike were drawn, tired.

Apparently that meant the battle was over. Soon the pain gun antennas were out of view and the effect ended. The Sil who had stayed came out of shelter, and a great mournful dirge sounded. Their voices merged in a long, rolling chant. They moved among the fractured bodies, turning them to the perpetual sun. The song rose up and reverberated from canyon walls. Quert splayed arms to the sky and joined in the deep long notes. It was eerie and moving and Cliff let himself be drawn into it for a long while, despite his pounding heart.

But at last the feeling ebbed. The flapping balloon creature was moving languidly away across an empty sky as teams crawled over it, mending. Quietly the humans left their post and Quert seemed to revive, shaking itself in quick vibrations of arms and legs, as if shaking off a mood. Quert led them away and into a long, narrow passageway through the far side of the ruddy canyon.

They walked in silence, absorbing what had happened.

“May return,” Quert warned. “Go.”

They hurried through an underground passage. They spent five minutes of running, pounding down channels as the chants behind faded away. Quert showed them what looked like an air lock and they went through it fast. Beyond was a dimly lit tunnel. In this they ran for at least half an hour, just Quert and five other of the aliens—who ran with unhurried grace, their paces light, long, and quick—and following them came the humans, slogging on with thumping feet.

Like gazelles, Cliff thought, and then went back to pondering what might lie ahead. He had led them into this and for quite a while now he had not known where it was going. Wandering and staying out of the hands of the Bird Folk had seemed obvious. Plus trying to learn—and those were the last things he had been certain of for a long time.