Challenge: Some villains managed to obtain a letter written to Santa. It was addressed to North Pole 34162578 and contained the message:

llHdeoeaanraSt,Iitwyreouthwniiteionttnownyaurothchaitrstsimpasutdaignnerxmbsya{_e_TihLt1_dlueRmM_beyr0}!

This is a really straight forward cypher, the address 34162578 is used to shuffle letters in 8 letter blocks. I couldn’t find an online tool for this fast enough, so I wrote a PHP scrip.

$o = "";
foreach (str_split($in, 8) as $chunk) {
	$ch = "        ";
	foreach (str_split($key) as $k=>$i) {
		$ch[intval($i)-1] = $chunk[$k];
	}
	$o .= $ch;
}

var_dump($o);

It was later, when I came back that I found an online tool: https://www.dcode.fr/transposition-cipher key = 34162578 mode = Write by rows, read by rows

Flag: xmas{_The_Lit1le_dRumMer_b0y}

What did I learn: Easier to find tools.