No. You're defining $level
AFTER the array has been parsed/executed/constructed by PHP. PHP cannot "reach back in time" to retroactively insert a value for $level
which didn't exist at the time you tried to insert $level
into the array when it was being parsed.
You'd have to do something like
$level = 'foo';
include('array_gets_defined_here.php');
echo $techniqueDescriptions['damage'];
Doing it the other way around:
include('array_gets_defined_here.php');
$level = 'foo';
echo $techniqueDescriptions['damage'];
gets you into the time travel situation.