From there, players can select a level to play from the world map, interact with non-player characters aboard the ship, listen to music at the jukebox, and spend their accrued Lucre to buy upgrades for Crow; these include health meter extensions, additional grenade ammunition, and equippable modifications that add special properties to Crow's attacks.

Infiltrating an Adept Co. laboratory in Macro City, Crow learns that Mayapple commissioned the villain Dr. Cackle to create an artificial princess made of energy to be her successor.

Mayapple, still feeling guilty, asks Crow to help her infiltrate Cackle's lab and stop him from creating more Farrah Days for global conquest.

As Crow returns to his home base in Bramble Flats to finish his plan, the Sovereign is attacked and destroyed by Tephra, who seeks the Doom Howitzer for herself and has united the other kingdoms' armies under her rule.

In the game's true ending, if Mayapple did not kill Cackle, Crow can choose to abandon the plan at the last moment out of friendship with the princesses.

Disgusted by his lack of ambition, Becky takes control of the Doom Howitzer, forcing Mayapple to stop her with help from Crow and the princesses.

In the aftermath, the princesses return to their kingdoms; Malachite and Ariella dethrone Tephra and end their people's war; and Mayapple rejects Mack's attempts to get back together.

[7] Kyle LeClair of Hardcore Gamer rated the game 4/5, praising the "boastful and charming character" and "cute sense of humor with some gorgeous graphics.

[8] In January 2018, game director Josh Hano began releasing a continuation of the Nefarious story in the form of an ongoing webcomic.

Set after the game's true ending, the comic sees Crow reconnect with his siblings and contend with other villains, including his father Buzzard, while Mack and Mayapple must navigate the complex political landscape of heroics and villainy.