The Invisible Tower by Nils Johnson-Shelton

extended the sword in front of him. The boat began to rock, and the buoy clanged against the gunwale.
    Artie knocked once against the side of the buoy. It made a dull thud. He counted to three.
    The sky turned black, and he didn’t know why. His hands tingled.
    â€œHurry, lad!” screamed Thumb.
    He knocked the pommel against its target again. As he counted, he looked up.
    The flock of birds suddenly dispersed, breaking from the center in all directions, leaving the giant bird all alone, its head twitching nervously back and forth.
    Artie knocked the sword a third time. Cleomede was getting hot to the touch.
    â€œArtie, hurry!” screamed Kay.
    A noise broke over them like a bomb going off. It was a huge, hollow, flapping sound, far worse than that of the magnificent Argentine.
    Artie craned and saw a long, iridescent green dragon twirling overhead, practically blotting out the entire sky.
    Kay shouted, “What the?”
    Then it dived. The magnificent Argentine had gone from hunter to prey.
    It banked defensively. Its wing tip cut the surface of the water, then it straightened and drove directly for the canoe.
    Artie held up Cleomede and tried to remember what Bercilak had told him to do next. But he couldn’t.
    The bird strafed them, its raptorlike feet bumping the buoy and shaking the canoe violently. Everyone grabbed the boat and held on for dear life.
    The dragon glided over them, moving through the air like a snake. Artie thought it looked more like a Chinese dragon than your typical European-style, Middle Earth kind of dragon. That didn’t make it any less terrifying, though.
    The giant bird was scared, but not for long, because in an instant the serpent plucked it from the sky. The dragon made horrible gurgling noises as it choked down its prey whole, the bird’s mighty feathered wings folding into the serpent’s mouth.
    They were stunned.
    The dragon licked its chops. The bulky, and still moving, form of the bird could be seen in the beast’s scaly belly. For a brief moment the monster seemed content.
    But then it looked straight at them and let out a wail that beat upon their hearts as much as it did upon their eardrums.
    It prepared to dive again.
    Thumb drew his sword and yelled, “Ask for the sword, boy!”
    Artie was momentarily paralyzed. Should he really be throwing the only magical blade in the boat away at a time like this?
    Kay screamed. The vorpal bunny, his long ears pulled over his straining black eyes, screamed too.
    Artie hoisted Cleomede above his head, shrieked, “Excalibur!” turned the sword to the water, and shoved it into the Lake’s depths, letting go of his only defense.
    The blade sluiced the water, and for a moment everything went black.

12
IN WHICH ARTIE ACQUAINTS HIMSELF WITH THE FIREBRAND EXCALIBUR
    The blackness lifted like a slow fade-up in a movie.
    Artie was still on the boat, still clutching the gunwale, still on one knee. His face was still contorted in a mask of fear and urgency.
    He eased his grip and relaxed his face.
    He blinked.
    Calmness washed over him.
    He looked at the water. Its surface was weird. It was still. No—it was moving. Only very, very slowly.
    The boat also moved slowly as it righted itself incrementally.
    Time was almost frozen.
    Artie looked into the canoe.
    Kay was on her butt, her face grimacing in confrontation. Vorpal was ready to pounce into the air and attack. Thumb stood at full height. He held his sword above him with both hands. His mouth was wide with fury and his eyes were lit like exploding stars. He looked very brave.
    Artie looked up, and there it was. A great green dragon. Bright and shimmering where the light hit it on the margins, dark and foreboding on the underside that rushed toward them.
    Or had been rushing toward them. Like everything else, the dragon was practically stock-still.
    Artie took the creature in. It was glorious. It had red rubied teeth and its golden horns were