My solution for https://ironscripter.us/a-powershell-cryptogram/

crypto_challange.ps1

$crypto = @"
P k T r 2 s z 2 * c F -
r a z 7 G u D 4 w 6 U #
g c t K 3 E @ B t 1 a Y
Q P i c % 7 0 5 Z v A e
W 6 j e P R f p m I ) H
y ^ L o o w C n b J d O
S i 9 M b e r # ) i e U
* f 2 Z 6 M S h 7 V u D
5 a ( h s v 8 e l 1 o W
Z O 7 l p K y J l D z $
- j I @ t T 2 3 R a i k
q = F & w B 6 c % H l y
"@

function Check-Decrypt($x, $y, $crypto){
    $crypto = $crypto.split() -join ''
    $current_variable = 'x'
    $Result = @()
    while($true){
        if ((Get-Variable $current_variable).value -gt $crypto.length){break}
        $Substring = $crypto.Substring(0, (Get-Variable $current_variable).value)
        $crypto = $crypto.TrimStart($Substring)
        $Result += $Substring[-1] 
        if ($current_variable -eq 'x'){$current_variable = 'y'}else{$current_variable = 'x'}
    }
   $Result -join ''
}
$xs = (1..20)
$ys = (1..20)
$i = 0
Write-Host
foreach ($x in $xs){
    foreach ($y in $ys){
        $r = Check-Decrypt -x $x -y $y -crypto $crypto
        Write-Host "[x:$x|y:$y] = $r"
        $i ++
        if (($i % 5) -eq 0){Read-Host -Prompt "Press ENTER key to get next 5 results or CTRL+C to quit"}
    }
}