Dead Rising 4 originally ends with Frank West falling from the clutches of a helicopter to his zombie bitten death. This is not the true ending however as the Frank Rising DLC continues the main story right from the that blank out area. Starting right from the point of Frank West gracefully falling to a horde of zombies below, the DLC starts with him getting eaten alive. It's actually somewhat dark and sad considering how iconic Frank is with this series.
Once the feeding has finished the zombies walk away a bloody corpse is left lying there on the pavement. It then tweaks and zombie Frank is born, this new deadlier version then heads out to eat. Things go well as he eats gingerbread people since I assume human characters were too time intensive to produce and meets some old friends.
They happily put him down and transfer him to doctor Dr. Blackburne for care. It would seem that she's at least somewhat cured the zombie plague and West becomes a hybrid. He has the aspects of what makes a zombie craze flesh while gaining broken English and eyes that glow a little less demented. While this does bring some fun abilities in, Frank desperately wants to be human.
After a string of fetch quests they hatch a plan to cure him from the threat until West get betrayed by the good doctor. He then goes and meets up with Hammond along with what's left of her crew to fight back.
The small group of survivors defends the barn location featured in the core game and then takes the assault to Blackburne. This causes the death of many soldiers and then Hammond's group comes in to defend the helipad that's going to evac them. While that's going on Frank runs through a procedure to cure himself and this comes at the expense of all remaining survivors of that Willamette group.
The ending cinematic shows Frank West and Dr. Blackburne in the back of a chopper in absolute dismay as they're carried away. A final message shows up on the screen giving clarity to Frank's life and while I don't believe it considering future games are coming it states the following.
Pentagon Press Release
January 5, 2022
Though Frank West escaped Willamette with his life, he eventually left the world of photojournalism and disappeared from the public eye.
No one ever learned of his time as a zombie. To his dying day, Frank was plagued by nightmares of death, blood and insatiable hunger...
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