Why isn't this if/elseif/else code working (Snippet-related)

<?php
$type = isset($type) ? $type : '-';
$atr = isset($atr) ? $atr : '-';
$target = isset($target) ? $target : 'Single enemy.';
$power = isset($power) ? $power : '-';
$fof = isset($fof) ? $fof : '-';
$learn = isset($learn) ? $learn: '-';
$sunlight = isset($sunlight) ? $sunlight : 'No effect.';
$fof_type = isset($fof_type) ? $fof_type : '-';
$fof_atr = isset($fof_atr) ? $fof_atr : '-';
$fof_target = isset($fof_target) ? $fof_target : 'Single enemy.';
$fof_power = isset($fof_power) ? $fof_power : '-';
$mystic_extension = isset($mystic_extension) ? $mystic_extension : '-';

$mystic_activation = preg_replace('/SB/','<b>',$mystic_activation);
$mystic_activation = preg_replace('/EB/','</b>',$mystic_activation);
$mystic_extension = preg_replace('/SB/','<b>',$mystic_extension);
$mystic_extension = preg_replace('/EB/','</b>',$mystic_extension);

$output = "";
if (isset($fof_name)) {
  $output .=  '<ul class="sectionselect"><li><strong>'.$name.' <em><small>'.$desc.'</small></em></strong></li></ul><p></p>

<div id="table">
<table cellspacing="3" cellpadding="3" class="setup">
<colgroup span="5">
 <col/>
 <col/>
 <col/>
 <col/>
 <col/>
</colgroup>

<tbody>
 <tr>
  <th class="heading">Type</th>
  <th class="heading">ATR</th>
  <th class="heading">TP</th>
  <th class="heading">Target</th>
  <th class="heading">Power</th>
 </tr>
 <tr>
  <td class="data">'.$type.'</td>
  <td class="data">'.$atr.'</td>
  <td class="data">'.$tp.'</td>
  <td class="data">'.$target.'</td>
  <td class="data">'.$power.'</td>
 </tr>
 <tr>
  <th class="heading" colspan="1">FOF Creation</th>
  <th class="heading" colspan="1">Learn</th>
  <th class="heading" colspan="3">FS Chambers</th>
 </tr>
 <tr>
  <td class="data" colspan="1">'.$fof.'</td>
  <td class="data" colspan="1">'.$learn.'</td>
  <td class="data-nc" colspan="2">
<b>Carmine</b>: '.$carmine.'<br />
<b>Cobalt</b>: '.$cobalt.'
  </td>
  <td class="data-nc" colspan="1">
<b>Grass</b>: '.$grass.'<br />
<b>Sunlight</b>: '.$sunlight.'
  </td>
 </tr>
 <tr>
  <th class="heading" colspan="2">FOF</th>
  <th class="heading" colspan="3">FOF Activator</th>
 </tr>
 <tr>
  <td class="data" colspan="2"><acronym title="'.$fof_desc.'" class="help">'.$fof_name.'</acronym></td>
  <td class="data" colspan="3">'.$activate.'</td>
 </tr>
 <tr>
  <th class="heading">Type</th>
  <th class="heading">ATR</th>
  <th class="heading">TP</th>
  <th class="heading">Target</th>
  <th class="heading">Power</th>
 </tr>
 <tr>
  <td class="data">'.$fof_type.'</td>
  <td class="data">'.$fof_atr.'</td>
  <td class="data">'.$fof_tp.'</td>
  <td class="data">'.$fof_target.'</td>
  <td class="data">'.$fof_power.'</td>
 </tr>
</tbody>
</table>
</div>
<p></p>';
} elseif (isset($mystic_activation)) {
  $output .= '<ul class="sectionselect"><li><strong>'.$name.'</li></ul><p></p>

<div id="table">
<table cellspacing="3" cellpadding="3" class="setup">
<colgroup span="5">
 <col/>
 <col/>
 <col/>
 <col/>
 <col/>
</colgroup>

<tbody>
 <tr>
  <th class="heading">Type</th>
  <th class="heading">ATR</th>
  <th class="heading">TP</th>
  <th class="heading">Target</th>
  <th class="heading">Power</th>
 </tr>
 <tr>
  <td class="data">'.$type.'</td>
  <td class="data">'.$atr.'</td>
  <td class="data">'.$tp.'</td>
  <td class="data">'.$target.'</td>
  <td class="data">'.$power.'</td>
 </tr>
 <tr>
  <th class="heading" colspan="5">Activation</th>
 </tr>
 <tr>
  <td class="data" colspan="5">'.$mystic_activation.'</td>
 </tr>
 <tr>
  <th class="heading" colspan="5">Extension</th>
 </tr>
 <tr>
  <td class="data" colspan="5">'.$mystic_extension.'</td>
 </tr>
</tbody>
</table>
<p></p>
</div>';
} else {
  $output .= '<ul class="sectionselect"><li><strong>'.$name.' <em><small>'.$desc.'</small></em></strong></li></ul><p></p>

<div id="table">
<table cellspacing="3" cellpadding="3" class="setup">
<colgroup span="5">
 <col/>
 <col/>
 <col/>
 <col/>
 <col/>
</colgroup>

<tbody>
 <tr>
  <th class="heading">Type</th>
  <th class="heading">ATR</th>
  <th class="heading">TP</th>
  <th class="heading">Target</th>
  <th class="heading">Power</th>
 </tr>
 <tr>
  <td class="data">'.$type.'</td>
  <td class="data">'.$atr.'</td>
  <td class="data">'.$tp.'</td>
  <td class="data">'.$target.'</td>
  <td class="data">'.$power.'</td>
 </tr>
 <tr>
  <th class="heading" colspan="1">FOF Creation</th>
  <th class="heading" colspan="1">Learn</th>
  <th class="heading" colspan="3">FS Chambers</th>
 </tr>
 <tr>
  <td class="data" colspan="1">'.$fof.'</td>
  <td class="data" colspan="1">'.$learn.'</td>
  <td class="data-nc" colspan="2">
<b>Carmine</b>: '.$carmine.'<br />
<b>Cobalt</b>: '.$cobalt.'
  </td>
  <td class="data-nc" colspan="1">
<b>Grass</b>: '.$grass.'<br />
<b>Sunlight</b>: '.$sunlight.'
  </td>
 </tr>
</tbody>
</table>
<p></p>
</div>';
}

return $output;
?>

[[arte-abyss? &name=`Fang Blade Havoc` &desc=`A combination of Fang Blade and Havoc Strike.` &type=`Physical` &tp=`16` &power=`310` &learn=`Lv15 + 50x Fang Blade/Havoc Strike` &carmine=`Damage +10%` &cobalt=`25% change of knockback.` &grass=`TP cost reduced by 1/8.`]]

$mystic_activation = preg_replace('/SB/','<b>',$mystic_activation);
$mystic_activation = preg_replace('/EB/','</b>',$mystic_activation);

if($mystic_activation !=""){
$mystic_activation = preg_replace('/SB/','<b>',$mystic_activation);
$mystic_activation = preg_replace('/EB/','</b>',$mystic_activation);
}