It's rare to see a natural bodybuilder or fitness enthusiast close to their genetic muscular potential gain more than 2-3 pounds of lean muscle in a year. This is why it's an accomplishment when experienced bodybuilders manage to gain 7-10 pounds of fat-free muscle in a year. Newbies gains are plenty real, but very delusional. Losing fat naturally makes you look more ripped, but 20lbs of muscle? I feel like neophytes simply don't know what 20 pounds of raw muscle looks like. You'd look like a beast....I.e. Hugh Jackman for wolverine. He has all the markers for tren, I'm not gonna dive in on the Rock since he's a walking Anavar commercial. You don't have to believe me, just do the research on every site, from bodybuilding.com to youtube/google, or shoot an email to a doctor.
Can you blow up in a year? Oh yeah, but you're gonna have a little gut/fat and or look "fluffy" ala a lot of NFL quarterbacks, even then....they're taking. Remember when people thought Mark Maguire was some physical freak? That's a guy who put on 10lbs of muscle....just 10, in a short time, and you can see how big he got. 20lbs of muscle is massive, and only achievable via gear. Genetic gods like Eugene Sandow were ripped before steroids, but again, he was naturally lean.