However, remember that a proxy merely allows you to access a blocked website.
The simplest way to know for sure if The Pirate Bay is down is to search Is Pirate Bay Down.
Some have pop-up ads and harmful malware that can easily damage your computer.
As per the laws of some countries, downloading torrents or using a torrent client is not illegal in itself since you can upload things that are not under copyright.
But some mirror sites, as is the case with most The Pirate Bay mirror sites, are created by people who have little to nothing to do with the sites they mirror.
The site has all sorts of torrent files that can be downloaded onto the computer, and used to stream videos, listen to music, and play games.