"What is that? Water?" Erix asked, seeing a large vial in Hal's hand. He held two smaller bottles in his other hand.

"No. They're magic potions of some kind. I took them when I escaped from the ship. I don't know why I did. Magic gives me the willies."

Erix's brows knitted. "What do they do?"

The howling echoed again, still distant. Corporal paced nervously while Hal thought about his answer.

"I don't know for sure. You drink them, and something magic happens. The labels explain it all, I'm sure, but I've never seen writing like this."

"Perhaps you should throw them away," urged the woman quietly. "We don't need them, and what if they're dangerous?"

"Oh, I don't know," Halloran said airily. "They might come in handy." He set the two small bottles back in the pack and unstoppered the large one. Squinting into the bottle first, he raised it and took a short sip.

"Halloran!"

When Erix screamed, Hal quickly dropped the bottle and spat. He fumbled to push the cork back in, wondering why he couldn't see the bottle. Come to think of it, he couldn't see his hands, either. He was invisible!

"Halloran? Where are you?" Erix whirled around, panicking.

"It's – it's all right. I'm right here." Already his form began to grow visible, and in moments, he looked normal again. "This is a potion of invisibility! I didn't take enough to do more than fade for a second, but if we need to, we can drink a dose and disappear!"

"Forever?" Erix was clearly dubious.

"No… for an hour or two, I suppose. I know they're only temporary, but I haven't had much experience with potions." He reached for one of the small bottles.

"Wait!" urged Erix. "It does seem that they may be useful, but let's leave the others for a later time. We should be moving on now."

The howling abruptly faded, changing in pitch and volume. They could still hear it, but it did not seem so imminent.

Corporal suddenly growled and sprang to his feet. A gust of wind swirled through the grotto, rippling the stream water and rustling the grass along the bank. Hal looked up but saw nothing, even though light still washed their camp. Once more the howling echoed in the distance. Then Corporal barked loudly.

The sound saved Halloran's life. He whirled to look behind him just in time to see a silver sword driving toward his throat. Twisting away, he leaped to his feet. A sudden wind blazed the dull coals of the fire back to light, and Hal gaped in astonishment at his attacker.

Or rather, his lack of an attacker. The silver sword danced in the air, apparently animated by itself. His astonishment grew as he saw the weapon clearly.

"That's Helmstooth – my own sword!" he cried. The blade, given to him by Cordell himself, had been taken away when he was arrested. Now, as if under its own power, it was attacking him!

As the weapon darted forward again, he saw splashes in the shallow water below it, marking the passage of invisible feet. He snatched the sword he had claimed from Alvarro from the nearby saddle and parried the attacker's next blow.

But the enchanted sword flickered back and forth too quickly for Hal's eye, and the legionnaire stumbled backward to avoid another deadly thrust. His shock turned to fear as he realized that this inanimate attacker could kill him. He tumbled backward through shallow water, and something splashed after him.

Corporal leaped at the attacker, snarling and biting at the air. The greyhound twisted in the water as a sudden gust of wind whipped up froth. A column of swirling air suddenly lifted the dog and hurled him to the shore.

Halloran darted at the invisible shape, hacking back and forth, trying to knock Helmstooth to the ground. The whirlwind turned back, and spray flew in a howling column, blinding Hal. The force of the air buffeted him backward, and he sprawled on the shore.

The once placid grotto became a cage to him now, the limestone walls barring him from maneuver… or flight. The rocky barriers formed a deadly arena, where life would be the winner's prize.

Halloran scrambled desperately to his feet as Helmstooth came at him again. Diving away, he once again tumbled headlong in his desperate attempt to evade death. The sword chopped at the ground behind him, and he rolled away, bumping his shoulder on a sharp object.

The sword lifted above him, ready for the kill, when something thumped into the invisible figure and knocked it aside. Hal saw Erix holding a sizable log, originally intended for their fire. But the whirlwind shape came swirling back, and Halloran knew they could not best it with physical attacks.

The sharp object jabbed at him again as he struggled to his feet, and he realized that he had fallen onto his backpack. The top of one of the small potion bottles was barely visible, jutting from the side pocket. It had been that bottleneck that had poked him.

Erix swung again, knocking the invisible sword-thing backward, but then the wind swirled around her, smashing her to the ground. Hal's throat tightened with a cold terror that dwarfed his earlier fear. Then the sword turned back toward him. It was not interested in killing Erixitl of Maztica.

Desperately Hal pulled the little bottle from the pack. I hope this does more than make me invisible. Popping the cork, he threw back the bottle and gulped its entire contents in one swallow. In the next instant, he raised his sword and parried another slashing blow.

Once again the swirling wind raced through the camp. Spray blinded Hal, and he braced himself for the crushing force that had twice knocked him over. Closing his eyes against the stinging needles of water and dirt, he leaned into the wind and struggled to keep his balance.

But the wind did not swirl so forcefully this time, at least, not against his whole body. He felt it pounding his belly and his legs, then just his legs. He opened his eyes as the spray fell into mist and the wind jerked, annoyingly but not dangerously, at his calves.

He looked down at the fire, down at Erix, saw the starlit horizon stretching for miles around the grotto… around the grotto! Even the twenty-foot high walls that had concealed their camp now looked like a trench around him. I'm a giant! he suddenly realized. For a moment, he reeled with vertigo, so dizzying was the sensation.

But his feet had grown proportionately, and his balance remained steady. He crouched lightly, dropping into the trenchlike grotto, every bit as nimble as he had ever been.

Halloran saw the silver sword slash in for another attack, and he kicked the irritating thing away. Slowly he grasped the significance of the potion: It had increased him to a height of perhaps thirty feet. His weapons and clothing had grown right along with him!

Erix sat, awestruck, gaping up at him. The invisible stalker whirled in again, and Hal raised one huge foot, stepping down hard on the struggling form. His massive weight pressed the thing into the water.

A froth of bubbles exploded around his giant foot, but he could feel the substance of the monster still wriggling beneath the pressing weight. For several minutes, he stood still, and slowly the struggles faded. Finally bubbles burst from the water all around his foot, as if a great air sack had burst.

Feeling nothing resisting him now, he reached down and plucked Helmstooth from the bottom of the stream. Holding the sword like a toothpick, he looked around for any sign of the attacker, but once again the night was silent.

Erix stammered something unintelligible, and once again he looked at her horrorstruck face.

"Don't worry," he soothed, his voice like the rumbling of thunder. "It won't last long."

At least, that's what he hoped.

"Up here, inside the mountain," explained Luskag, barely breaking a sweat. "That's where we'll find the Sunstone."