This small Chrome extension allows you to retrieve all magnet links situated in the current tab and copy them directly into the clipboard, separated by newlines. This way, you can just go on your favourite Torrent Client and paste all of them in the "magnet links" box ready to download.
Just download all the files and place them in a single folder. Then, navigate to chrome://extensions, make sure developer options is enabled and click "load unpacked", uploading your folder. That's it!