I cannot spot a mistake right now, but here is the whole code looking a bit more nicely:
Code:

---

action enemy_fight // attached to the enemy
{
	enemy = me; // I'm the enemy
	enemy.healthpoints = 100; // and I have 100 healthpoints
	
	while (my.healthpoints > 0) // as long as I'm alive
	{
		if (vec_dist (my.x, player.x) < 200 && player.healthpoints > 0) // the player approaches the enemy
		{
			vec_set(temp, player.x);
			vec_sub(temp, my.x);
			vec_to_angle(my.pan, temp);
			my.tilt = 0; // I'm a maniac
			enemy_distance.x = 5 * time;
			enemy_distance.y = 0;
			enemy_distance.z = 0;
			ent_move(enemy_distance, nullvector);
			ent_cycle("walk", my.skill19); // play walk frames animation
			my.skill19 += 5 * time; // "walk" animation speed
			
			if (my.skill19 > 100) {my.skill19 = 0;} // loop animation
			if (vec_dist (my.x, player.x) < 50) // if the player comes closer than 50 quants attack him
			{
				my.skill20 = 0; // reset "attack" frames
				
				while (my.skill20 < 100)
				{
					ent_vertex(my.sword_tip, 291); // sword tip vertex coords - get the value in Med
					ent_vertex(my.sword_base, 306); // sword base vertex coords - get the value in Med
					trace_mode = ignore_me + ignore_passable;
					trace (my.sword_base, my.sword_tip); // trace between these sword positions
					
					if (result != 0) // hit something, could be the player or another enemy
					{
						if (you != null) {you.healthpoints -= 4 * time;}
					}
					
					ent_cycle("attack", my.skill20); // play attack frames animation
					my.skill20 += 5 * time; // "attack" animation speed
					
					wait (1);
				}
				
				waitt (6); // slows down the enemy and reduces the number of traces per second
			}
		}
		else // the player is farther than 200 quants away
		{
			ent_cycle("stand", my.skill21); // play stand frames animation
			my.skill21 += 2 * time; // "stand" animation speed
			if (my.skill21 > 100) {my.skill21 = 0;} // loop animation
		}			
		
		wait (1);
	}
	
	while (my.skill22 < 80) // the enemy is dead
	{
		ent_cycle("death", my.skill22); // play death frames animation
		my.skill22 += 1 * time; // "death" animation speed
		wait (1);
	}

	my.passable = on; // the corpse can't be hit by the sword from now on
}

---

hi, i clear the bracket and modified the code in some cases, is equal but more nicely...and i have other error lol, (sorry for the much questions but i am begginer), look the update code:

(the fields in red colour are the updates)

Code:

---

  
var player_distance; // moves the player
var enemy_distance; // moves the enemy
var distance;

define sword_base = skill12; // using skill12, 13, 14 to store the sword_base coords
define sword_tip = skill15; // using skill15, 16, 17 to store the sword_tip coords
define healthpoints = skill18; // just another name for skill18

entity* enemy;

action enemy_fight // attached to the enemy
{
	 distance = vec_dist (my.x, player.x); 
	enemy = me; // I'm the enemy

	enemy.healthpoints = 100; // and I have 100 healthpoints
	 while(!player) { wait(1); }  // wait until the player exists
	{
		 if (distance < 200)  // the player approaches the enemy
		{
			vec_set(temp, player.x); 
			vec_sub(temp, my.x);
			vec_to_angle(my.pan, temp);
			my.tilt = 0; // I'm a maniac :)
			enemy_distance.x = 5 * time;		
			enemy_distance.y = 0;
			enemy_distance.z = 0;
			ent_move(enemy_distance, nullvector);
			ent_cycle("walk", my.skill19); // play walk frames animation
			my.skill19 += 5 * time; // "walk" animation speed
			if (my.skill19 > 100) {my.skill19 = 0;} // loop animation
			if (vec_dist (my.x, player.x) < 50) // if the player comes closer than 50 quants attack him
			{
				my.skill20 = 0; // reset "attack" frames
				while (my.skill20 < 100)
				{
					ent_vertex(my.sword_tip, 291); // sword tip vertex coords - get the value in Med
					ent_vertex(my.sword_base, 306); // sword base vertex coords - get the value in Med
					trace_mode = ignore_me + ignore_passable;
					trace (my.sword_base, my.sword_tip); // trace between these sword positions
					if (result != 0) // hit something, could be the player or another enemy
					{
						
						if (you != null) {you.healthpoints -= 4 * time;}
						
					}
					ent_cycle("attack", my.skill20); // play attack frames animation
					my.skill20 += 5 * time; // "attack" animation speed				
					wait (1);
				}
				waitt (6); // slows down the enemy and reduces the number of traces per second
			}
		}
		else // the player is farther than 200 quants away
		{
			ent_cycle("stand", my.skill21); // play stand frames animation
			my.skill21 += 2 * time; // "stand" animation speed
			if (my.skill21 > 100) {my.skill21 = 0;} // loop animation
		}
		wait (1);
	 
	while (my.skill22 < 80) // the enemy is dead
	{
		ent_cycle("death", my.skill22); // play death frames animation
		my.skill22 += 1 * time; // "death" animation speed
		wait (1);
	}

	my.passable = on; // the corpse can't be hit by the sword from now on
}

---

Good, put me error in ejecution: "Empty pointer in enemy_fight: distance=vec_dist(my.x,player.x)"

Help me please. bye

the player is not initialised yet

make a wait at the beginning:

action enemy_fight // attached to the enemy
{
wait(1);



or:

action enemy_fight // attached to the enemy
{
while(player==null){wait(1);}

Hi Democles, look, the error is solved, now compile and run and the error not visible but the enemy... not move . What is the problem now? the enemy would that attack the player at the 50 quants...but the enemy NOT MOVE. Help me again please, is important.

did you set the pointer to your player???

action player_move
{
player = me;
...

Thanks you all!!!!!!!!!! Problem solved! thank you kasimir!!

@Xarthor:
just a question, i was playing around with your code a bit, and changed a few things to see if it would attack the template plbiped01_entity. the code ran with no errors, but when the level started, i got an error saying "invalid arguements in enemy_fight: ent_animate(@2, my.skill21)", then a crash afterwards saying the same thing. what did i miss?

here's the modification:
Code:

---

var enemy_distance; // moves the enemy
var distance;
define sword_base = skill12; // using skill12, 13, 14 to store the sword_base coords
define sword_tip = skill15; // using skill15, 16, 17 to store the sword_tip coords
define healthpoints = skill18; // just another name for skill18
entity* enemy;
action enemy_fight // attached to the enemy
{
while(plBiped01_entity==null){wait(1);}
   	   distance = vec_dist (my.x, plBiped01_entity.x); 	
   	   enemy = me; // I'm the enemy	
   	   enemy.healthpoints = 100; // and I have 100 healthpoints	 
   	   while(!plBiped01_entity) { wait(1); }  // wait until the player exists	
   	   {
   	           if (distance < 200)  // the player approaches the enemy		
   	           {
   	                  vec_set(temp, plBiped01_entity.x); 			
   	                  vec_sub(temp, my.x);			
   	                  vec_to_angle(my.pan, temp);		
   	                 	my.tilt = 0; // I'm a maniac :)			
   	                 	enemy_distance.x = 5 * time_step;					
   	                 	enemy_distance.y = 0;			
   	                 	enemy_distance.z = 0;			
   	                 	ent_move(enemy_distance, nullvector);			
   	                 	ent_animate("walk", my.skill19); // play walk frames animation			
   	                 	my.skill19 += 5 * time_step; // "walk" animation speed			
   	                 	if (my.skill19 > 100) {my.skill19 = 0;} // loop animation			
   	                 	if (vec_dist (my.x, plBiped01_entity.x) < 50) // if the player comes closer than 50 quants attack him			
   	                 	{
   	                          my.skill20 = 0; // reset "attack" frames				
   	                          while (my.skill20 < 100)				
   	                          {
   	                                  ent_vertex(my.sword_tip, 291); // sword tip vertex coords - get the value in Med					
   	                                  ent_vertex(my.sword_base, 306); // sword base vertex coords - get the value in Med					
   	                                  trace_mode = ignore_me + ignore_passable;					
   	                                  trace (my.sword_base, my.sword_tip); // trace between these sword positions					
   	                                  if (result != 0) // hit something, could be the player or another enemy					
   	                                  {	
   	                                           if (you != null) {you.healthpoints -= 4 * time_step;
   	                                  }											}					
   	                                  ent_animate("attack", my.skill20); // play attack frames animation					
   	                                  my.skill20 += 5 * time_step; // "attack" animation speed									
   	                                  wait (1);				
   	                          }				
   	                          wait (6); // slows down the enemy and reduces the number of traces per second			
   	                  }		
   	          }		
   	          else // the player is farther than 200 quants away		
   	          {			
   	                  ent_animate("stand", my.skill21); // play stand frames animation			
   	                  my.skill21 += 2 * time_step; // "stand" animation speed			
   	                  if (my.skill21 > 100) {my.skill21 = 0;} // loop animation	
   	          }		
   	          wait (1);
   	          	 	
   	   while (my.skill22 < 80) // the enemy is dead	
   	   {
   	           ent_animate("death", my.skill22); // play death frames animation		
   	           my.skill22 += 1 * time_step; // "death" animation speed		
   	           wait (1);	
   	   }	
   	   my.passable = on; // the corpse can't be hit by the sword from now on
}  

---

You have to be carefull with "ent_animate". The ent_animate instruction expects an entity pointer as first argument:

Quote:

---

ent_animate(ENTITY* entity,STRING* scene,var percent,var mode)

---

Thus you need to change all your ent_animate instructions:
Simply add a "my," in the instruction.
Example:
ent_animate(me,"stand",my.skill21,ANM_CYCLE);

thanks a lot Xarthor, but now i have another issue. the level runs with no errors, but the enemy is dead when i approach it. what should i do?