PHP en radio buttons

<?php
// Check if session is already running or not
if (!session_id()) session_start();


// Include connection/header
include_once "connect.php";
include_once "up_html.php";


// Check for session "player"
if (isset($_SESSION['player']))
{
	//Find player within session
	$playersess = mysql_real_escape_string($_SESSION['player']);
	$sql_users = "SELECT * FROM km_users WHERE playername = '" . $playersess . "'";
	
	// Check if query "km_users" could run
	if ($result_users = mysql_query( $sql_users ))
	{
		$player = mysql_fetch_array($result_users); ?>
        
        <table class="maintable">
            <tr class="headline"><td><center>Select Monster to Slay</center></td></tr>
            <tr class="mainrow"><td>
            <form method="post">
            <?php
				$sql_monsters = "SELECT * FROM km_monsters ORDER BY skill ASC";
				
				// Check if query "km_monsters" could run
				if ($result_monsters = mysql_query( $sql_monsters ))
				{
					// While loop the results
					while ($monsters = mysql_fetch_array($result_monsters))
					{
						$totalskill = $player['skillpts'] + $monsters['stats'];
						$chance = ($player['skillpts'] / $totalskull * 100);
						$chance = round($chance, 0, PHP_ROUND_HALF_UP); ?>
                        
                        <input type="radio" name="monstername" value="<?php echo $monsters['name']; ?>" checked><b><?php echo $monster['name']; ?></b><br>
                        <p><?php echo $chance; ?> chance, reward: <?php echo $monster['goldworth']; ?> gold</p><hr>
                        
                        <?php
					}
				}
				else {
					// Query could not run
					echo "Error running query, contact the administrator.";
				}
			?>
            
            <br>
            <input type="submit" name="submit" value="Hunt Animal">
            </form>
            </td></tr>
      	</table>
        
        <?php	
		// Run form submit
		if (isset($_POST['submit']))
		{
			// Player has no more turns
			if ($player['numturns'] < 1) {
				echo 'You need at least 1 turn to kill a monster, please go back to <a href="index.php">Main</a>';
			}
			else {
				// Turns left, run the page
				$monstername = mysql_real_escape_string($_POST['monstername']);
				$sql_monster = "SELECT * FROM km_monsters WHERE name = '" . $monstername . "'";
				
				// Check if query "km_monsters" could run
				if ($result_monsters = mysql_query( $sql_monsters ))
				{
					$monsters = mysql_fetch_array($result_monsters);
					
					// Calculate monsters
					$totalskill = $player['skillpts'] + $monsters['skill'];
					$randnumber = rand(1, $totalskill);
					$chance = ($player['skillpts'] / $totalskill * 100);
					
					if ($randnumber <= $player['skillpts'])
					{
						$gained = $monsters['pointsifkilled'];
						$gold = $monster['goldworth'];
						
						$sql_users = "UPDATE km_users SET skillpts = skillpts + '" . $gained . "', gold = gold + '" . $gold . "' WHERE playername = '" . $playersess . "'";
						
						if ($result = mysql_query( $sql_users )) { ?>
                        
                        	<center><img src="images/knight.gif"></center>
                            You slay the <?php echo $monster['name']; ?> is glorius combat and gained <?php echo $gained; ?> skillpts
                            <center><a href="index.php">Kill more monsters</a></center>
                        
                       	<?php
						}
						else {
							// Could not run query
							echo "Error running query, please contact the administrator.";
						}
					}
					else {
						// Lost battle from monster ?>
                        
                        <center><img src="images/defeat.gif"></center>
                        <?php echo $chance; ?> The <?php echo $monster['name']; ?> laughs as you run away from the battle like a chicken<br><br>
                        <a href="index.php">Kill more monsters</a>
                        
                        <?php
					}
				}
				else {
					// Could not run query
					echo "Error running query, please contact the administrator";
				}
			}
		}
	}
	else {
		// Could not run query
		echo "Error running query, please contact the administrator";
	}
}
else {
	// Player is not logged in
	echo 'You are not logged in, please <a href="login.php">Login</a>';
}


// Include footer
include_once "down_html.php";