The site has most cartoon series I can think of for free streaming, and has been around for a long time. Most of the series there are not in HD though, but the Lion Guard happens to be. You have to sit through quite a few commercials to watch most things, but you'd be doing that if you watched them on TV too.
You can watch them on KissCartoon in 720p. http://kisscartoon.me/Cartoon/The-Lion-Guard The site
