All eyes were on Na'dia as she followed Ninat and Peyral to the group of single women. An anonymous foot was slid in front of her, and she tripped. Only slamming into Peyral's broad back stopped her from falling flat on her face. Her clumsiness provoked a ripple of laughter.

"Sorry," she said to Peyral, who nodded in reply.

They found a small vacant area and squatted, waiting for the food to be passed around on leaf plates. While Peyral held the leaf for her, Na'dia picked at the some of the food, struggling to chew and swallow, and not throw up. She was shaking inside, praying that she did not show her fear. This was as bad as waiting to go on stage on opening night. No, it was worse.

She could very well die in the next few minutes.

A voice cried out, "Olo'eyktan, why is there a tawtute among the Omaticaya, lurking like a lenay'ga in the undergrowth, ready to kill us in the dark of night?"

A broad-shouldered Na'vi warrior stood up, wearing the shaven head and beads of a warrior. Na'dia was shocked to recognise wheelchair guy – Jake Sully. The only sign that he had been ever been human were his large hands, and he looked as tough and ruthless as all hell. "I See you, Tsaylu," said Sully. "I only know of Na'vi in this place."

The warrior that had called out stood. He said, "What of the dreamwalker woman? She is not Omaticaya." There was a murmur of agreement from many of the tribe.

Sully replied, "It is true. Na'diakhudoshin is not Omaticaya, though she passed through the Eye of Eywa. Can you say the same of yourself?"

Tsaylu said, "Where is the proof of that? All know that tawtute lie. They are cowardly and cunning, and are not to be trusted."

"I was tawtute," said Sully. "Do you accuse me of lying? Do you accuse me of betrayal?"

"You are Toruk Makto," said Tsaylu. "You are Omaticaya, and led the united clans to victory against the tawtute. You we do not doubt, but the dreamwalker woman we do not know."

Na'dia saw Txep'ean start to move, so she stood up before he could speak. "I am Na'diakhudoshin, warrior. Many of you here saw my tawtute body die, scarred with the fire of their science. Why should I betray the Na'vi for those that tortured me?"

"Who can know what a tawtute thinks?" snarled Tsaylu.

Calm now that she had taken action, Na'dia replied, "Do you challenge me?"

"Yes," announced the angry male.

The tribe stirred with excitement. Sully shouted over the noise, "Tsahik Mo'at shall judge the challenge. The Omaticaya cannot afford the loss of another warrior."

Tsaylu laughed, and much of the tribe laughed with him. Apparently they thought there was little chance of him losing. "Agreed," said Na'dia. "I do not wish to injure this man, if it can possibly be avoided."

This calm statement provoked even more hilarity.

A space cleared in the middle of the tribe for the mismatched two to fight.

Ninat stood by Na'dia, passing her the shortswords which she had brought into the eating place. "Why are you making him angry?" asked Ninat. "Do you know what you are doing? Tsaylu is one of the best warriors in the clan."

"He has never fought me," replied Na'dia, pretending confidence that she did not feel. The monster was well over a foot taller than her, and both out-muscled and out-massed her by a substantial margin. The only trump card she had was that Tsaylu would never have encountered taekkyon sword dancing.

She swallowed when one of his friends passed him a fighting staff, the massive weapon carrying vicious bone blades at each end. It would be difficult to get inside the reach of the weapon, although her sensei on Earth had trained her against similar staves. When she drew her blades from their scabbards, there was a disturbing murmur at the sight of the dull grey titanium alloy blades. The only metal that the Na'vi had ever seen were weapons and vehicles made by the tawtute.

Na'dia asked, "Ninat, do you know tic-tac-toe?"

"The tawtute children's game?" said her friend, her voice carrying over the noise of the tribe. "Of course I do." She looked puzzled.

"Good," said Na'dia, taking up her starting position, one blade held over her head, the other lowered, pointing at the ground, hoping like hell this was going to work, and waiting for the huge Na'vi warrior to attack.

Which he did, yelling as he ran at her, the staff raised over his head, obviously trying to dispatch her with his first blow through sheer strength. The idiot was wide open.

Na'dia spun in, not even parrying his blow, slipping inside his reach, slashing with each sword once across his chest, barely making contact, and then skidding down to the ground behind him.

Tsaylu turned, more quickly than she could have thought possible, swinging his staff low to catch her. God, he was fast. She managed to leap above the staff, somersaulting in an impossible move for a human – but not for her Avatar body. As she landed on her feet, she made another double slash downwards. The touches were so light she doubted he had even felt them, and she spun out of his reach.

"Very pretty," he sneered, ignoring the beading of blood on his chest, the cross shape of the four shallow slashes just barely visible.

"Centre," she said, waiting for him to move.

He moved more cautiously this time, trying to pick up her twitch, the indication she made before moving. But she had been taught from early childhood by one of the masters of taekkyon, a major in the Ukrainian army and fanatic martial artist. She had done it mainly to improve her strength, her agility, and her mental focus for ballet, though the lessons had stuck, even after all this time. There had been one other reason why she had submitted willingly to the relentless discipline.

She slipped under his guard again, and made two slashes, a diagonal cross appearing in the middle of the cross-hatch in the middle of his chest. This time she parried his blow, deflecting it slightly to one side into the ground, the power of Tsaylu's blow sinking the staff deep into the soil.

Ninat called out "Top right."

As she exited his reach, a small vertical cross appeared on Tsaylu's chest, this time in the top right had corner of the cross hatch.

Na'dia called out "Top left."

As she attacked while Tsaylu tugged his staff out of the soil, Ninat called out, "Bottom right."

Crosses appeared in the top left and bottom right corners, when Mo'at called out "Halt!"

The two combatants froze, and backed away from each other. The crowds was deathly silent. Na'dia whispered to herself, "Thank you, Daddy." She hoped he would be proud of her. She had tried so hard to follow his teachings, and not to use his art to hurt someone. A tear pricked at her eye as she realised how much she missed him, even after all these years.

Mo'at announced, "Na'diakhudoshin has proven herself in combat. Tsaylu, your assertion is false. Eywa has spoken."

"What!" he shouted, not believing what he heard.

The Tsahik pointed at his chest and said, "She could have slain you with any of those blows, but chose not to. Every cut was exactly where she wanted it to be."

Tsaylu stood there dumbfounded, as Na'dia bowed deeply to the Tsahik out of habit, as she always bowed to her sensei after a bout.

"Na'dia, watch out!" yelled Ninat.

She twisted out of the bow, to see Tsaylu swinging the staff down at her. There was no time. The ruthless fighting machine that her father had ingrained into her brain over sixteen years made an instant calculation. She could not sever a limb – the blades would jam on his carbon-fibre reinforced bones. If she tried to do that, the blow would not stop. There was only one thing she could do.

As she spun one blade went high, making a great cut through Tsaylu's throat, severing the major blood vessels to his brain and slashing open his gullet, the tip of the blade barely scratching the front of his vertebrae.

The other blade went low, striking less than half a second afterwards, spilling open his belly in a huge diagonal upward slash. The staff slipped from his hands and the Na'vi warrior collapsed at the knees, crashing to the ground in front of Na'dia, a wave of blood and guts covering her feet and splattering her with red.

Na'dia stopped in the same position she had started the bout, a picture of deadly grace, as a bead of blood dripped off her lower blade. The tribe was shocked by the speed with which she had despatched one of their best warriors, without apparent effort, even though she was the victim of a surprise attack and had been totally off-balance.

The petite Na'vi girl lowered her blades to her side and sank to her knees, weeping for her lost innocence.