Tank is so tough that he breaks FR.
Tank is so tough that he eats pineapples for breakfast, lunch, and DINNER... without cutting them open first.
Tank is so tough that he smashes coconuts with his head.
Tank is so tough that his neck has more muscles than your whole body.
Tank is so tough that he once strangled a mire toad with his neck.
Tank is so tough that his belly crushes mantarunes.
Tank is so tough that when golem workshop bosses see him, they immediately malfunction.
Tank is so tough that he gets all the bog ladies AND the snap ladies.
Tank is so tough that when he visits Plague, diseases run for their lives.
Tank is so tough that the Stormcatcher gave him a day off.
Tank is so tough that the Lightweaver comes to personally light his cave.
Tank is so tough that the Tidelord parts the waters for him.
Tank is so tough that when the Windsinger sent a hurricane to fight him, Tank walked out without a frill out of place.
Tank is so tough that the Flameforger crowned him 'King of Fire' even though he's an ice dragon.
Tank is so tough that when the Icewarden tried to freeze him solid, Tank called it a 'refreshing shower'
Tank is so tough that he didn't have to brew skink, Baldwin just saw him and handed it right over.
Tank is so tough that Chuck Norris has nightmares about him.
Tank is so tough that when Sockknitter kitted Tank a sweater, it turned into solid dragonsteel armor the second Tank put it on.
Tank is so tough that he cuts knitting yarn with his sword.
Tank is so tough that he weightlifts with his tongue.
Tank is so tough that when fodder dragons see him, they exalt themselves.

As Tank has traveled Sornieth, we have learned more about his incredible toughness: