Heyya! If you go to
https://marvel.com/insider/rewards and buy the "Carnage Starter Bundle" for 10k points, you can get a 2* Carnage! (And some other stuff) But fair warning:
A. 2* is the only option,
2. Carnage isn't that great of a champ,
and three. It won't deliver until mid-July.
But if you wanna try him out and see what he's like, it's an option. And I'm sure at least one person reading this didn't know.