The last DLC for the "Batman: Arkham Knight" Season Pass has finally arrived.

The "Season of Infamy" DLC is considered the biggest expansion pack out of all the downloadable releases for the action-adventure game.

The "Season of Infamy" DLC comes with several missions that stars four of the most notorious enemies of the Dark Knight, namely the Mad Hatter, Killer Croc, Ra's al Ghul, and Mr. Freeze. The villains will be reunited in Gotham where they need to make sure that they are more ruthless than the rest.

The new downloadable content comes with several story arcs that feature the four villains. Mr. Freeze was the center of the events in "In From The Cold," while Ra's Al Ghul torments Batman in "Shadow War," which was said to be one of the most awaited content in the pack because of its numerous side plots.

Meanwhile, the Mad Hatter will come in the DLC's Knight Crusader in the "Wonderland" arc,which was said to be the easiest content in the pack, while the Killer Croc will join the "Beneath The Surface" plot complete with several platforming sequences and a few combat.

According to a post on the PlayStation blog, creating the four important characters for the DLC was not an easy task.

"Each character model was built from scratch to make the most of the game engine updates and give you, our fans, visually new-gen super-villains," the post explained.

Those who are already subscribed to the "Season of Infamy" DLC can also get the last Batmobile that was dubbed the Original Arkham Batmobile that can be added to the player's Bat-garage.

Also, the new DLC comes with the 2008 Movie Batman Skin, which players can use and post using the game's share button to upload on social media websites.

The "Batman: Arkham Knight Season of Infamy" DLC came out on Dec. 22.