Need help with an online puzzle from m4tr1x.ws

I found this online riddle at m4tr1x.ws, but now I am stuck. It seems you need to gain deeper and deeper access to this virtual Matrix-style computer system. First you need to create an account via the register command. That is easy, after confirming via email you can login to the system.

Afterwards you need to connect to the site via a Tor browser. It turned out the address to connect via Tor is “matrix4ozv2gicar.onion”. Connected via Tor you can login again with your user and issue the command redpill tor.

Now you gained level 2 of this riddle. Writing just redpill now gives you the following:

bruteforce SHA224: f6d54a854ca1d0e987b798e1593de79631b8f2329fb84a15725bf9b2

And here I am stuck. I have no idea how to decrypt that string. Does one really have to brute-force it? That doesn’t feel like the real answer to that problem. I tried several Matrix-related phrases and words, but without success.

Any ideas?