PHP - Trouble adding value to third dimensional array
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I have a this array scenario at first:

    $_SESSION['player_1_pawn'][] = 'Warrior';

now when I want to add a third dimensional value like this:

    $_SESSION['player_1_pawn'][0]['x'] = 1;

I get this output from $_SESSION['player_1_pawn'][0] : '1arrior'

My question is that, how to make that value stays intact as 'Warrior' instead of '1arrior'?