Chapter IV: What the Hell? is the fourth chapter in the story.
Chapter IV takes place in Hell, directly after Sola Soulhawk murdured everyone in Chapter III. This chapter's theme is consistently bad, undesirable things happening to the heroes, as the are in Hell.
The boss was Bobby Kotick.
Following the deaths of the Smoosh members at the hands of Sola, Luna and the others awaken to find themselves n a fiery and brimstone-covered landscape. Not only are they shocked by the uniniviting new scenery around them, but it also occurs to the heroes that Nicois missing from the group. Ace attempts to use the Nintendoki DS to call Nintendoki for help, only to discover that the communication device has no reception. Soon after, Hades appears before the heroes to announce that they have been sent to Hell, and will be forced to suffer for all eternity. After being questioned by Washington, Hades mentions that he was once the ruler of the Underworld, but after Christianity took over as one of the most common systems of belief, Hades was demoted and control of the underworld was given to the devil, who renamed it Hell. The god of the dead then leaves the heroes to wallow in their misery.
Eventually, Frost gets an idea in order to help the group escape. Using his water-manipulation abilities, Frost creates a radio tower out of ice to give the Nintendoki DS a good enough reception to contact Nintendoki. Although the message Nintendoki proceeds to give the heroes is filled with static, the manage to decipher that Nintendoki will only help them escape Hell if they first obtain one of the items on his list that is located there: a piece of lava from the center of the earth.
With this new information, Eddie calls for Hades to come back so they can strike a deal: If Hades can help them find Nico and the item on Nintendoki's list, Smoosh will help Hades get rid of the devil and reclaim control of the Underworld. Hades, though skeptical, accepts this deal, but on one additional condition: Hades states that he has recently met a "foxy" woman who's currently staying at his bachelor pad, and he will help Smoosh if they can hook him up with said woman. Assuming that said "foxy" character is Nico, Washington is reluctant to go through with this, but Eddie insists that if they ever want to see the world of the living again, they have no choice but to play along.
Hades leads the group of heroes to his house, which is located in the City of Dis. On the way there, the group notices a Gamestop selling another one of the items on Nintendoki's list: Guitar Hero 19. But, this being Hell and all, the cost of said game is "one maiden sacrifice". By creating a dummy out of gum using Luna's gumweaving abilities and Washington's alchemical powers to disguise it as a real maiden, the decoy is taken to the Gamestop (being puppeteered by Mortal) and exchanged for Guitar Hero 19. Nintendoki, who's apparently improved the reception on the Nintendoki DS since their last call, congratgulates the team and insists that they press onward.
Upon finally arriving at Hades's house, the group discovers that the woman Hades was referring to was not Nico at all, but actually Hoar. Many of the members of Smoosh become enraged due to the fact that they still have no idea where Nico is, but they realize that they still have to honor their part of the bargain by hooking up Hades with Hoar. They decide to do this by preparing a romantic dinner for the two, although this backfires horribly when they discover tyhat Hoar is allergic to gourmet food, cauding her to vomit all over Hades's house before running off.
Enraged, Hades blames Smoosh for this and proceeds to lock them up in his basement and forces them to watch a nonstop marathon of High School Musical as punishment. As the group comtemplates a way to escape, Shigeru Miyamoto appears, and, with the help of Mortal, frees Smoosh from their prison.
Having obtained information that the only gateway to the center of the earth is located at the lowest circle of Hell, Luna attempts to formulate a strategy in order for Smoosh to get there. Through an unexpected turn of events, Jack accidentally kills a group of children, resulting in such a major sin that the group is rocketed down to the lowest circle.
In contrast to the hot, fiery landscape of the usual Hell, the group discovers that this circle is unbearably cold and frozen. While searching for the gateway to the center of the earth, the group encounters a zombified Chibi. Seeing as the creature has grown much stronger since their last fight, Smoosh has no choice but to run away.
As they try to escape Chibi, a group of Oni Demons riding on pegasi appear and attempt to stop the heroes. After some fast-paced combat, the group manages to fight off the demons and escape Chibi.
After escaping via a transport copter summoned by Jack, the group finds themself in the courtyard of an ominous castle. There they find Nico, who has been brainwashed by none other than the devil, who turns out to be none other than the CEO of Activision, Bobby Kotick. When Smoosh demands that Nico should be set free, Kotick becomes enraged and attacks the heroes with a wave of Guitar Hero-esque music notes. In an effort to fend off these notes, Washington, Frost and Eddie grab some guitars and play the notes as if they were part of a Guitar Hero song, thus distracting Kotick while the others attack.
Near the end of the fight, Nico manages to break free of Kotick's mind control and proceeds to blast him with fire, burning off his outer skin and revealing his true form- a small, weak creature reminiscent of Gollum. Hades appears just in time to deal the finishing blow to Kotick, and brings Smoosh the lava they needed as gratitude for helping him regain control of Hell, which he has changed back to the Underworld.
Smoosh is sent back to the world of the living via the power of HAX, thus concluding the chapter.
-Depending on one's belief, Chapter IV can either be the second Chapter based on a non-fictional place, or the third in a fictional one.