Mr. Fusion Home Energy Reactor Achievement
Mr. Fusion Home Energy Reactor5
Collect any Minikit within the 'Back to the Future!' level
There are 10 minkits in the level. You only need to collect one to unlock this achievement. Renting characters can be another way to get one of the minikits faster. You can also enter cheat code "JYJAFX" by pressing to activate the Minikit Detector cheat.
The easiest minikit in this level to get is during the Mall scene where the bandits circle around Doc's Van. You will need Batman or a character with grapple to obtain it.
Here is a video guide on some of the minikits in this level: