rTorrent is an efficient, command-line only BitTorrent client that uses the libTorrent library as its underlying engine.
rTorrent can be compiled and run on nearly every POSIX-compliant system, including Linux, FreeBSD and OS X. It is often used in conjunction with GNU Screen or Tmux for remote torrent downloading.
There are several front-ends for rTorrent available, the most popular ones are ruTorrent and flood, with pyrocore is slowly becoming a competent interface.
How to download magnet links with rTorrent
Method 1 : rTorrent has support for magnet links since v0.8.7 released back in October 2010. In order to load a magnet link, just hit backspace while you’re using rTorrent and paste the link.
Method 2 : Alternatively, you can use any online magnet link converter to turn it into a torrent file, then load it into rTorrent. Torrent2Magnet by Calpe Consulting is a nice one with simple interface. Please note that you should not use this site for private magnet links, as it makes your magnet publicly available after converting.
Method 3 : ruTorrent allows you to add magnet links easily by pasting the URL into Torrent URL in Add Torrent window.