The Penguin (Batman: Assault on Arkham)

A brutal and sadistic crime lord, Oswald Chesterfield Cobblepot is known in the Gotham City Underworld as The Penguin and funds much of its criminal operations as one of its biggest black market manufactures. Directing his affairs from the Iceberg Lounge, Oswald was seen as a reputable business man to the people of Gotham, but was a sadistic, mass murdering gang leader in reality.

Batman: Assault on Arkham
At some point prior to the events of the film, Penguin had initially hired the Joker and Harley Quinn with delivering a truck presumably containing contraband material to his forces. However, this resulted in them dumping the truck and its contents into the river, thus costing Penguin a fortune, thus earning him a bitter grudge against Harley Quinn. He also held a lot of respect for Deadshot for his reputation of being among the best assassins out in the criminal underworld.

He was eventually contacted by Amanda Waller with supplying the Suicide Squad with a way into Arkham Asylum, and supplied them with a file allowing access into the Asylum. However, when he saw that Harley Quinn was among the group, he attempted to gun her and the others down in his rage against her for her earlier ruining of one of his operations. However, he was eventually talked out of it by Deadshot when the latter pointed out that him killing his clients would reflect badly on him and allowed them to leave, although under the condition that they not appear in his sight again, especially with Harley Quinn.

Trivia

 * The Penguin's feasting on raw fish and octopi during his meeting with the Suicide Squad was a reference to the Penguin's dietary habits in Batman Returns.