| rowspan="2" style="text-align:center;"|'''In order to play these maps on hard, you must complete the previous map on either normal or hard.'''<br/> ''(e.g., to do E-4 on hard, you must complete E-3 on normal or hard.)'' | | rowspan="2" style="text-align:center;"|'''In order to play these maps on hard, you must complete the previous map on either normal or hard.'''<br/> ''(e.g., to do E-4 on hard, you must complete E-3 on normal or hard.)'' |