Well, it wont ever work
PHP Code:
// WRONG!
'arcade => $vbphrase['arcade_hack_templates'],
PHP Code:
// CORRECT!
'arcade' => $vbphrase['arcade_hack_templates'],
Syntax Error Heaven
Plus, vBulletin automatically suffixes the phrases (be they vb'ed or not) with "Templates", so yours would read "Arcade Hack Templates Templates", if you included "Templates" in the vbphrase you add