Step 1: Open https://www.hackthebox.eu/invite
Step 2 : Right click on page and select inspect as below :

Step 3: Then find below

Step 4 : Type the address as below :

Step 5 : Copy the output as below :

Step 6 : Go to http://deobfuscatejavascript.com/ and paste the code there as below :

Step 7 : Click on below button to decode the code :

Step 8 : Find makeInviteCode() from below :

Step 9 : Click on console as below :

Step 10 : Type makeInviteCode() and hit enter in console window

Step 11 : copy below from above :

Step 12 : Go to https://rot13.com/ and paste the data as below to encode as below :

Step 12 : Go to browser and type url as below :

Step 13 : Go to terminal or command prompt and type below :

Step 14 : Copy the code like below :

Step 15 : Go to https://www.base64decode.org/ and paste the code to decode
Step 16 : You will get a code like below :

Then you are done . Just past the code in below and you will get registration window:
