Rudy Jones was a janitor at STAR Labs. In search of easy money, Rudy checked some containers believing there was hidden cash. The container that Rudy opened actually had a special radiation Darkseid had left there in order to create a new menace to mankind. Rudy became a being able to absorb people's energy (and powers, if they have) known as the Parasite. He was briefly an enemy of Firestorm, but finally settled in trying to get Superman's power.
Lego Batman 3
Parasite along with Vibe and Zamaron Warrior can be unlocked via Free Play, in the mission "Power of Love".