[store_unit]
    [filter]
        type=Blood Core
        [filter_location]
            find_in=core_locs
        [/filter_location]
    [/filter]
    variable=shuffle_stack
    kill=yes
[/store_unit]

{REVERSE_FOREACH shuffle_stack k}

    {VARIABLE r -1}

    [if]
        {VARIABLE_NUMERICAL_GREATER_THAN k 0}
        [then]
            {VARIABLE_RANDOM r "0..$($k - 1)"}

            {VARIABLE swap.x $shuffle_stack[$r].x}
            {VARIABLE swap.y $shuffle_stack[$r].y}

            {VARIABLE shuffle_stack[$r].x $shuffle_stack[$k].x}
            {VARIABLE shuffle_stack[$r].y $shuffle_stack[$k].y}

            {VARIABLE shuffle_stack[$k].x $swap.x}
            {VARIABLE shuffle_stack[$k].y $swap.y}

            [unstore_unit]
                variable="shuffle_stack[$r]"
                find_vacant=yes
            [/unstore_unit]

            {CLEAR_VARIABLE swap}
        [/then]
    [/if]

    [unstore_unit]
        variable="shuffle_stack[$k]"
        find_vacant=yes
    [/unstore_unit]

    {CLEAR_VARIABLE shuffle_stack[$k]}

    [if]
        {VARIABLE_NUMERICAL_GREATER_THAN r -1}
        [then]
            {CLEAR_VARIABLE shuffle_stack[$r]}

            {VARIABLE_DEC k}
        [/then]
    [/if]

    {CLEAR_VARIABLE r}

{REVERSE_NEXT k}