If I find a website offering a 'Scott Pilgrim comic pdf free download,' how can I determine if it's a legitimate source?

Generally, if a website is offering the entire Scott Pilgrim comic series as a free PDF download, it is highly likely to be an illegitimate source. Official publishers and retailers do not typically offer entire comic series as free downloads. Look for official branding (Oni Press), secure website connections (HTTPS), and verifiable contact information. If the offer seems too good to be true, it probably is.