1. There's plenty of Pixar to it.
2. It's set in a city that's a hybrid of San Francisco and Tokyo.
3. Its hero, Hiro, is biracial.
4. Baymax is a marvel of cuteness engineering.
Diversity aside, nifty composite city setting aside, there's Big Hero 6's breakout character. The round, squishy heart, and thing everyone will be talking about after seeing the movie, is Baymax, the robot who accompanies Hiro on his battle against a mysterious masked villain who's stolen the nanobot tech Hiro invented. Baymax has been re-imagined as a medical robot its designer deliberately chose to make out of inflatable vinyl for extra approachability — it's durable and strong, but also like a giant marshmallow that comes with its own first aid kit. Baymax gets leveled up and given some handy armor and additions, but its main concerns are still the health and well-being of Hiro and his friends.
Baymax is the result of some genius-level adorable character design, waddling away from danger ("I am not fast," it unnecessarily notes), inflating itself like an air mattress, fixing leaks with tape, and attempting to fist-bump, which it accompanies with a sound that's never not funny. As voiced by Adsit, Baymax is warmly but mechanically even-keeled in everything, but it's the physical comedy that comes from how Baymax moves and reacts to things that makes the character so instantly endearing.