Yes, the original base game is Villainous: The Worst Takes It All - here's a link to the manufacturer's page:
https://www.ravensburger.us/product...us-the-worst-takes-it-all-60001739/index.html
Though I think you can find it for like $5 less on
Amazon.
The green box with Maleficent's silhouette is the right one. There is a newer version of the base game that was streamlined; basically, they took out two villains and made it a little easier, but is otherwise the same, and that one is called Introduction to Evil (Ursula silhouette on the box). I recommend the original because it's fun to play as different villains.
Indeed there are a lot of versions, including Marvel and Star Wars. You can't mix the Marvel and Star Wars with the Disney villains. But you can mix all Disney animation villains together in one game. So, sticking with just the Disney animation villains that can all play with each other, here are the expansions in order of release:
- Villainous: The Worst Takes It All (Maleficent, Queen of Hearts, Hook, Ursula, Prince John, and Jafar) - 2018
- Villainous: Wicked to The Core (Evil Queen, Hades, and Dr. Facilier) - 2019
- Villainous: Evil Comes Prepared (Ratigan, Scar, and Yzma) - 2019
- Villainous: Perfectly Wretched (Cruella De Vil, Mother Gothel, and Pete) - 2020
- Villainous: Despicable Plots (Gaston, The Horned King, and Lady Tremaine) - 2021
- Villainous: Bigger and Badder (Lotso, Syndrome, Madam Mim) - 2022
- Villainous: Filled with Fright (Oogie Boogie) - 2023
- Villainous: Sugar and Spite (King Candy and Shere Khan) - will be released June 2024
Any two or more of these can play in one game together. You don't need the original game to start, you could buy an expansion by itself and play as long as you have at least two villains.