The stillness of the forest trail was so primeval that the tread of a soft-booted foot was a startling disturbance. At least it seemed so to the ears of the wayfarer, though he was moving along the path with the caution that must be practised by any man who ventures beyond Thunder River. He was a young man of medium height, with an open countenance and a mop of tousled tawny hair unconfined by cap or helmet. His garb was common enough for that country—a coarse tunic, belted at the waist, short leather breeches beneath, and soft buckskin boots that came short of the knee. A knife-hilt jutted from one boot-top. The broad leather belt supported a short, heavy sword and a buckskin pouch. There was no perturbation in the wide eyes that scanned the green walls which fringed the trail. Though not tall, he was well built, and the arms that the short wide sleeves of the tunic left bare were thick with corded muscle.

He tramped imperturbably along, although the last settler's cabin lay miles behind him, and each step was carrying him nearer the grim peril that hung like a brooding shadow over the ancient forest.

He was not making as much noise as it seemed to him, though he well knew that the faint tread of his booted feet would be like a tocsin of alarm to the fierce ears that might be lurking in the treacherous green fastness. His careless attitude was not genuine; his eyes and ears were keenly alert, especially his ears, for no gaze could penetrate the leafy tangle for more than a few feet in either direction.

But it was instinct more than any warning by the external senses which brought him up suddenly, his hand on his hilt. He stood stock-still in the middle of the trail, unconsciously holding his breath, wondering what he had heard, and wondering if indeed he had heard anything. The silence seemed absolute. Not a squirrel chattered or bird chirped. Then his gaze fixed itself on a mass of bushes beside the trail a few yards ahead of him. There was no breeze, yet he had seen a branch quiver. The short hairs on his scalp prickled, and he stood for an instant undecided, certain that a move in either direction would bring death streaking at him from the bushes.

A heavy chopping crunch sounded behind the leaves. The bushes were shaken violently, and simultaneously with the sound, an arrow arched erratically from among them and vanished among the trees along the trail. The wayfarer glimpsed its flight as he sprang frantically to cover.

Crouching behind a thick stem, his sword quivering in his fingers, he saw the bushes part, and a tall figure stepped leisurely into the trail. The traveler stared in surprise. The stranger was clad like himself in regard to boots and breeks, though the latter were of silk instead of leather. But he wore a sleeveless hauberk of dark mesh-mail in place of a tunic, and a helmet perched on his black mane. That helmet held the other's gaze; it was without a crest, but adorned by short bull's horns. No civilized hand ever forged that head-piece. Nor was the face below it that of a civilized man: dark, scarred, with smoldering blue eyes, it was a face untamed as the primordial forest which formed its background. The man held a broadsword in his right hand, and the edge was smeared with crimson.

'Come on out,' he called, in an accent unfamiliar to the wayfarer. 'All's safe now. There was only one of the dogs. Come on out.'

The other emerged dubiously and stared at the stranger. He felt curiously helpless and futile as he gazed on the proportions of the forest man—the massive iron-clad breast, and the arm that bore the reddened sword, burned dark by the sun and ridged and corded with muscles. He moved with the dangerous ease of a panther; he was too fiercely supple to be a product of civilization, even of that fringe of civilization which composed the outer frontiers.

Turning, he stepped back to the bushes and pulled them apart. Still not certain just what had happened, the wayfarer from the east advanced and stared down into the bushes. A man lay there, a short, dark, thickly-muscled man, naked except for a loin-cloth, a necklace of human teeth and a brass armlet. A short sword was thrust into the girdle of the loin-cloth, and one hand still gripped a heavy black bow. The man had long black hair; that was about all the wayfarer could tell about his head, for his features were a mask of blood and brains. His skull had been split to the teeth.

'A Pict, by the gods!' exclaimed the wayfarer.

The burning blue eyes turned upon him.

'Are you surprised?'

'Why, they told me at Velitrium and again at the settlers' cabins along the road, that these devils sometimes sneaked across the border, but I didn't expect to meet one this far in the interior.'

'You're only four miles east of Black River,' the stranger informed him. 'They've been shot within a mile of Velitrium. No settler between Thunder River and Fort Tuscelan is really safe. I picked up this dog's trail three miles south of the fort this morning, and I've been following him ever since. I came up behind him just as he was drawing an arrow on you. Another instant and there'd have been a stranger in Hell. But I spoiled his aim for him.'

The wayfarer was staring wide-eyed at the larger man, dumfounded by the realization that the man had actually tracked down one of the forest-devils and slain him unsuspected. That implied woodsmanship of a quality undreamed, even for Conajohara.

'You are one of the fort's garrison?' he asked.

'I'm no soldier. I draw the pay and rations of an officer of the line, but I do my work in the woods. Valannus knows I'm of more use ranging along the river than cooped up in the fort.'

Casually the slayer shoved the body deeper into the thickets with his foot, pulled the bushes together and turned away down the trail. The other followed him.

'My name is Balthus,' he offered. 'I was at Velitrium last night. I haven't decided whether I'll take up a hide of land, or enter fort-service.'

'The best land near Thunder River is already taken,' grunted the slayer. 'Plenty of good land between Scalp Creek—you crossed it a few miles back—and the fort, but that's getting too devilish close to the river. The Picts steal over to burn and murder—as that one did. They don't always come singly. Some day they'll try to sweep the settlers out of Conajohara. And they may succeed—probably will succeed. This colonization business is mad, anyway. There's plenty of good land east of the Bossonian marches. If the Aquilonians would cut up some of the big estates of their barons, and plant wheat where now only deer are hunted, they wouldn't have to cross the border and take the land of the Picts away from them.'

'That's queer talk from a man in the service of the Governor of Conajohara,' objected Balthus.

'It's nothing to me,' the other retorted. 'I'm a mercenary. I sell my sword to the highest bidder. I never planted wheat and never will, so long as there are other harvests to be reaped with the sword. But you Hyborians have expanded as far as you'll be allowed to expand. You've crossed the marches, burned a few villages, exterminated a few clans and pushed back the frontier to Black River; but I doubt if you'll even be able to hold what you've conquered, and you'll never push the frontier any further westward. Your idiotic king doesn't understand conditions here. He won't send you enough reinforcements, and there are not enough settlers to withstand the shock of a concerted attack from across the river.'

'But the Picts are divided into small clans,' persisted Balthus. 'they'll never unite. We can whip any single clan.'

'Or any three or four clans,' admitted the slayer. 'But some day a man will rise and unite thirty or forty clans, just as was done among the Cimmerians, when the Gundermen tried to push the border northward, years ago. They tried to colonize the southern marches of Cimmeria: destroyed a few small clans, built a fort-town, Venarium—you've heard the tale.'

'So I have indeed,' replied Balthus, wincing. The memory of that red disaster was a black blot in the chronicles of a proud and war-like people. 'My uncle was at Venarium when the Cimmerians swarmed over the walls. He was one of the few who escaped that slaughter. I've heard him tell the tale, many a time. The barbarians swept out of the hills in a ravening horde, without warning, and stormed Venarium with such fury none could stand before them. Men, women and children were butchered. Venarium was reduced to a mass of charred ruins, as it is to this day. The Aquilonians were driven back across the marches, and have never since tried to colonize the Cimmerian country. But you speak of Venarium familiarly. Perhaps you were there?'

'I was,' grunted the other. 'I was one of the horde that swarmed over the hills. I hadn't yet seen fifteen snows, but already my name was repeated about the council fires.'

Balthus involuntarily recoiled, staring. It seemed incredible that the man walking tranquilly at his side should have been one of those screeching, blood-mad devils that had poured over the walls of Venarium on that long-gone day to make her streets run crimson.

'Then you, too, are a barbarian!' he exclaimed involuntarily.

The other nodded, without taking offence.

'I am Conan, a Cimmerian.'

'I've heard of you.' Fresh interest quickened Balthus' gaze. No wonder the Pict had fallen victim to his own sort of subtlety. The Cimmerians were barbarians as ferocious as the Picts, and much more intelligent. Evidently Conan had spent much time among civilized men, though that contact had obviously not softened him, nor weakened any of his primitive instincts. Balthus' apprehension turned to admiration as he marked the easy cat-like stride, the effortless silence with which the Cimmerian moved along the trail. The oiled links of his armor did not clink, and Balthus knew Conan could glide through the deepest thicket or most tangled copse as noiselessly as any naked Pict that ever lived.

'You're not a Gunderman?' It was more assertion than question.

Balthus shook his head. 'I'm from the Tauran.'

'I've seen good woodsmen from the Tauran. But the Bossonians have sheltered you Aquilonians from the outer wildernesses for too many centuries. You need hardening.'

That was true; the Bossonian marches, with their fortified villages filled with determined bowmen, had long served Aquilonia as a buffer against the outlying barbarians. Now among the settlers beyond Thunder River there was growing up a breed of forest-men capable of meeting the barbarians at their own game, but their numbers were still scanty. Most of the frontiersmen were like Balthus—more of the settler than the woodsman type.

The sun had not set, but it was no longer in sight, hidden as it was behind the dense forest wall. The shadows were lengthening, deepening back in the woods as the companions strode on down the trail.

'It will be dark before we reach the fort,' commented Conan casually; then: 'Listen!'

He stopped short, half crouching, sword ready, transformed into a savage figure of suspicion and menace, poised to spring and rend. Balthus had heard it too—a wild scream that broke at its highest note. It was the cry of a man in dire fear or agony.

Conan was off in an instant, racing down the trail, each stride widening the distance between him and his straining companion. Balthus puffed a curse. Among the settlements of the Tauran he was accounted a good runner, but Conan was leaving him behind with maddening ease. Then Balthus forgot his exasperation as his ears were outraged by the most frightful cry he had ever heard. It was not human, this one; it was a demoniacal caterwauling of hideous triumph that seemed to exult over fallen humanity and find echo in black gulfs beyond human ken.

Balthus faltered in his stride, and clammy sweat beaded his flesh. But Conan did not hesitate; he darted around a bend in the trail and disappeared, and Balthus, panicky at finding himself alone with that awful scream still shuddering through the forest in grisly echoes, put on an extra burst of speed and plunged after him.

The Aquilonian slid to a stumbling halt, almost colliding with the Cimmerian who stood in the trail over a crumpled body. But Conan was not looking at the corpse which lay there in the crimson-soaked dust. He was glaring into the deep woods on either side of the trail.

Balthus muttered a horrified oath. It was the body of a man which lay there in the trail, a short, fat man, clad in the gilt-worked boots and (despite the heat) the ermine-trimmed tunic of a wealthy merchant. His fat, pale face was set in a stare of frozen horror; his thick throat had been slashed from ear to ear as if by a razor-sharp blade. The short sword still in its scabbard seemed to indicate that he had been struck down without a chance to fight for his life.

'A Pict?' Balthus whispered, as he turned to peer into the deepening shadows of the forest.

Conan shook his head and straightened to scowl down at the dead man.

'A forest devil. This is the fifth, by Crom!'

'What do you mean?'

'Did you ever hear of a Pictish wizard called Zogar Sag?'

Balthus shook his head uneasily.

'He dwells in Gwawela, the nearest village across the river. Three months ago he hid beside this road and stole a string of pack-mules from a pack-train bound for the fort—drugged their drivers, somehow. The mules belonged to this man'—Conan casually indicated the corpse with his foot—'Tiberias, a merchant of Velitrium. They were loaded with ale-kegs, and old Zogar stopped to guzzle before he got across the river. A woodsman named Soractus trailed him, and led Valannus and three soldiers to where he lay dead drunk in a thicket. At the importunities of Tiberias, Valannus threw Zogar Sag into a cell, which is the worst insult you can give a Pict. He managed to kill his guard and escape, and sent back word that he meant to kill Tiberias and the five men who captured him in a way that would make Aquilonians shudder for centuries to come.

'Well, Soractus and the soldiers are dead. Soractus was killed on the river, the soldiers in the very shadow of the fort. And now Tiberias is dead. No Pict killed any of them. Each victim—except Tiberias, as you see—lacked his head—which no doubt is now ornamenting the altar of Zogar Sag's particular god.'

'How do you know they weren't killed by the Picts?' demanded Balthus.

Conan pointed to the corpse of the merchant.

'You think that was done with a knife or a sword? Look closer and you'll see that only a talon could have made a gash like that. The flesh is ripped, not cut.'

'Perhaps a panther——' began Balthus, without conviction.

Conan shook his head impatiently.

'A man from the Tauran couldn't mistake the mark of a panther's claws. No. It's a forest devil summoned by Zogar Sag to carry out his revenge. Tiberias was a fool to start for Velitrium alone, and so close to dusk. But each one of the victims seemed to be smitten with madness just before doom overtook him. Look here; the signs are plain enough. Tiberias came riding along the trail on his mule, maybe with a bundle of choice otter pelts behind his saddle to sell in Velitrium, and the thing sprang on him from behind that bush. See where the branches are crushed down.

'Tiberias gave one scream, and then his throat was torn open and he was selling his otter skins in Hell. The mule ran away into the woods. Listen! Even now you can hear him thrashing about under the trees. The demon didn't have time to take Tiberias' head; it took fright as we came up.'

'As you came up,' amended Balthus. 'It must not be a very terrible creature if it flees from one armed man. But how do you know it was not a Pict with some kind of a hook that rips instead of slicing? Did you see it?'

'Tiberias was an armed man,' grunted Conan. 'If Zogar Sag can bring demons to aid him, he can tell them which men to kill and which to let alone. No, I didn't see it. I only saw the bushes shake as it left the trail. But if you want further proof, look here!'

The slayer had stepped into the pool of blood in which the dead man sprawled. Under the bushes at the edge of the path there was a footprint, made in blood on the hard loam.

'Did a man make that?' demanded Conan.

Balthus felt his scalp prickle. Neither man nor any beast that he had ever seen could have left that strange, monstrous three-toed print, that was curiously combined of the bird and the reptile, yet a true type of neither. He spread his fingers above the print, careful not to touch it, and grunted explosively. He could not span the mark.

'What is it?' he whispered. 'I never saw a beast that left a spoor like that.'

'Nor any other sane man,' answered Conan grimly. 'It's a swamp demon—they're thick as bats in the swamps beyond Black River. You can hear them howling like damned souls when the wind blows strong from the south on hot nights.'

'What shall we do?' asked the Aquilonian, peering uneasily into the deep blue shadows. The frozen fear on the dead countenance haunted him. He wondered what hideous head the wretch had seen thrust grinning from among the leaves to chill his blood with terror.

'No use to try to follow a demon,' grunted Conan, drawing a short woodsman's ax from his girdle. 'I tried tracking him after he killed Soractus. I lost his trail within a dozen steps. He might have grown himself wings and flown away, or sunk down through the earth to Hell. I don't know. I'm not going after the mule, either. It'll either wander back to the fort, or to some settler's cabin.'

As he spoke Conan was busy at the edge of the trail with his ax. With a few strokes he cut a pair of saplings nine or ten feet long, and denuded them of their branches. Then he cut a length from a serpent-like vine that crawled among the bushes near by, and making one end fast to one of the poles, a couple of feet from the end, whipped the vine over the other sapling and interlaced it back and forth. In a few moments he had a crude but strong litter.

'The demon isn't going to get Tiberias' head if I can help it,' he growled. 'We'll carry the body into the fort. It isn't more than three miles. I never liked the fat fool, but we can't have Pictish devils making so cursed free with white men's heads.'

The Picts were a white race, though swarthy, but the border men never spoke of them as such.

Balthus took the rear end of the litter, onto which Conan unceremoniously dumped the unfortunate merchant, and they moved on down the trail as swiftly as possible. Conan made no more noise laden with their grim burden than he had made when unencumbered. He had made a loop with the merchant's belt at the end of the poles, and was carrying his share of the load with one hand, while the other gripped his naked broadsword, and his restless gaze roved the sinister walls about them. The shadows were thickening. A darkening blue mist blurred the outlines of the foliage. The forest deepened in the twilight, became a blue haunt of mystery sheltering unguessed things.

They had covered more than a mile, and the muscles in Balthus' sturdy arms were beginning to ache a little, when a cry rang shuddering from the woods whose blue shadows were deepening into purple.

Conan started convulsively, and Balthus almost let go the poles.

'A woman!' cried the younger man. 'Great Mitra, a woman cried out then!'

'A settler's wife straying in the woods,' snarled Conan, setting down his end of the litter. 'Looking for a cow, probably, and—stay here!'

He dived like a hunting wolf into the leafy wall. Balthus' hair bristled.

'Stay here alone with this corpse and a devil hiding in the woods?' he yelped. 'I'm coming with you!'

And suiting action to words, he plunged after the Cimmerian. Conan glanced back at him, but made no objection, though he did not moderate his pace to accommodate the shorter legs of his companion. Balthus wasted his wind in swearing as the Cimmerian drew away from him again, like a phantom between the trees, and then Conan burst into a dim glade and halted crouching, lips snarling, sword lifted.

'What are we stopping for?' panted Balthus, dashing the sweat out of his eyes and gripping his short sword.

'That scream came from this glade, or near by,' answered Conan. 'I don't mistake the location of sounds, even in the woods. But where——'

Abruptly the sound rang out again—behind them; in the direction of the trail they had just quitted. It rose piercingly and pitifully, the cry of a woman in frantic terror—and then, shockingly, it changed to a yell of mocking laughter that might have burst from the lips of a fiend of lower Hell.

'What in Mitra's name——' Balthus' face was a pale blur in the gloom.

With a scorching oath Conan wheeled and dashed back the way he had come, and the Aquilonian stumbled bewilderedly after him. He blundered into the Cimmerian as the latter stopped dead, and rebounded from his brawny shoulders as though from an iron statue. Gasping from the impact, he heard Conan's breath hiss through his teeth. The Cimmerian seemed frozen in his tracks.

Looking over his shoulder, Balthus felt his hair stand up stiffly. Something was moving through the deep bushes that fringed the trail—something that neither walked nor flew, but seemed to glide like a serpent. But it was not a serpent. Its outlines were indistinct, but it was taller than a man, and not very bulky. It gave off a glimmer of weird light, like a faint blue flame. Indeed, the eery fire was the only tangible thing about it. It might have been an embodied flame moving with reason and purpose through the blackening woods.

Conan snarled a savage curse and hurled his ax with ferocious will. But the thing glided on without altering its course. Indeed it was only a few instants' fleeting glimpse they had of it—a tall, shadowy thing of misty flame floating through the thickets. Then it was gone, and the forest crouched in breathless stillness.

With a snarl Conan plunged through the intervening foliage and into the trail. His profanity, as Balthus floundered after him, was lurid and impassioned. The Cimmerian was standing over the litter on which lay the body of Tiberias. And that body no longer possessed a head.

'Tricked us with its damnable caterwauling!' raved Conan, swinging his great sword about his head in his wrath. 'I might have known! I might have guessed a trick! Now there'll be five heads to decorate Zogar's altar.'

'But what thing is it that can cry like a woman and laugh like a devil, and shines like witch-fire as it glides through the trees?' gasped Balthus, mopping the sweat from his pale face.

'A swamp devil,' responded Conan morosely. 'Grab those poles. We'll take in the body, anyway. At least our load's a bit lighter.'

With which grim philosophy he gripped the leathery loop and stalked down the trail.