Big Time released their first Medium article back on May 11th and the article does a great job of describing exactly what the game will be like.
“Big Time is a cooperative RPG that combines fast-action combat, the collectability of NFTs, and a history-spanning adventure. Big Time will take you on a wild ride across the vast reaches of time and space. Along the way, you’ll encounter some of history’s most famous (and infamous) figures… but don’t be surprised when they turn out a little different than you expected!”
You can learn more about Big Time by reading the full article here: What is Big Time?