All enemies "can" drop. Anything like that is a rare chance even in the early levels. It likely seems long do to the time it takes you to kill each mob.
I'm getting a "An error occurred running the Unity content on this page. See your browser's JavaScript console for more info. The error was:
TypeError: eventHandler.target is null" Error.
You need to 1: Get the super villains weapons after defeating them.
2: After defeating each be able to start a new game and play as them. Even being able to fight and defeat the PC.
Yeah...we have a fix coming for that