:-)

dd if=/dev/zero bs=1G count=10 | gzip -c > 10GB.gz

<?php
if (ipIsBlackListed() || isMalicious()) {
    header("Content-Encoding: gzip");
    header("Content-Length: "+ filesize(ZIP_BOMB_FILE_10G)); // 10 MB
    readfile(ZIP_BOMB_FILE_10G);
    exit;
}
?>

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