XSS Challenge

I found a link to an active XSS challenge, and i solved it. The goal was to do alert(1) using the query search, but it was quite complicated, because the website had an annoying security system.

You can try it on your own here

Sample alert: https://research.insecurelabs.org/puzzlers/xss1/?query=%27-au{6c}eu{72}t(%22i%22%2B%22z%22%2B%22a%22%2B%22n%22%2B%22b%22%2B%22f%22%2B%221%22%2B%228%22%2B%220%22%2B%223%22))%0A--%3E