The hook_cron_pre_execute($function, &$hook) is invoked just before running the cron function.
Call another function instead of the defined
function hook_cron_pre_execute($function, &$hook) {
if ($function == 'node_cron') {
$hook['callback'] = 'mymodule_steal_cron_function_from_node_module';
}
}
function mymodule_steal_cron_function_from_node_module() {
error_log('PWNED');
}