In fact, besides a bizarre confrontation between the Governor and his own people on the road from the prison back to Woodbury, nobody at all died for most of the episode--and not only did the Governor survive, but his two most trusted and untrustworthy henchmen did, as well. It was a bizarre episode.
In any event, his survival, his status as a series regular next year and some comments made by Robert Kirkman and the show's producers have left us wondering what might be next for a mad Governor with no one to govern.
One thing that's clear is that next season won't play the same games that this one did, in terms of building up a major confrontation between the Governor and Rick. Kirkman, Gale Anne Hurd, incoming showrunner Scott Gimple and pretty much anyone else who has any authority to speak has been saying that it's the year of the zombie--that after two years where the most credible threats to the group have been Shane and then the Governor, it feels as though the walkers are too manageable a threat, and the people in charge aren't comfortable with that.
That puts the Governor in the odd position of taking a demotion from central antagonist to...well, whatever role he's going to play. There are any number of possibilities.
The first and most obvious possibility is that he'll simply launch a surprise attack at some point in the season. Ideally this would be the midseason finale, to give the fans some resolution on the Governor's story and allow the rest of the year to continue on with a minimum of distraction, but as we saw this season, the showrunners won't always decide to go with predictable route of having the big events happen on finales and premieres.
In the case of a surprise attack, the most obvious choice (for a number of reasons) would be to approximate what's actually in the comics. Why? Because the sequence is iconic, so missing it would cause some consternation and disappointment among comics fans. It's also visually interesting and exciting to have someone zombies swarming a live tank as it takes down the prison walls.
A final showdown similar to what happened in the comics would also set him up for another iconic moment--the beheading of one of Rick's men outside the city gates. Some fans had speculated that Andrea might stand in for that character in the season three finale, but while she did die, it was never going to be at the hands of the Governor. At least not directly.
Another possibility--and this one toys with the fact that we don't know where the Governor, Shupert and Martinez were headed when they left the scene of the massacre in season three's finale--is that the Governor and his men could turn out to already be in the prison.
After all, the title of the season three finale was "Welcome to the Tombs," a reference to the largely unexplored lower levels of the prison. What if that's where the Governor and his men are holed up, waiting for an opportunity?
It's not out of the question; besides the fact that we don't actually know where they went, there's the fact that they had managed to watch Rick and his people, totally unobserved, as is evidenced by the Governor's remark that Rick and his group had brought in an impressive arsenal. Could whatever that vantage point was also lend them an opportunity to enter the building? Maybe--and certainly the map that Tyreese's people drew for them, which obviously included the broken segment of the fence and prison where they had entered in the first place.
Having an enemy within--and one they're totally ignorant of--could have some real storytelling possibilities for Team Prison.
The other side of that, of course, is that they could circle around and head for Woodbury. The Governor seemed to be manipulating the populace at will during his time in charge, in spite of having said and done some pretty crazy stuff. Could he think that he was heading to a manageable situation with his homecoming? And if the place is empty, could he set up camp there, or at least take what supplies they can carry out of town? The most dangerous situation they could encounter at Woodbury would be an ambush by someone Rick had watching the town, but it doesn't seem like the "let's set up a nursing home and live in peace" version of Rick would be willing to risk one or more of his people in the hopes of killing someone who, at face value, doesn't seem to present a threat.
That decision--if Rick made it--would likely set up a confrontation between he and Carl, who will almost certainly be chomping at the bit to put the Governor in the ground.
Another strong option for the Governor--and one that wouldn't have required Morrissey to be a series regular, except that regulars on The Walking Dead regularly die, and they might not have wanted to cast doubt on the duration of his stay--is that the Governor and his men could have been left alive simply to convey the scope of the next threat.
After all, what would make The Hunters or Negan more bad-ass than taking out the Governor and his men during the two-minute cold open of the season four premiere? Or even, given his proclivity for surviving everything the world throws at him, just conveying the size and menace of a particular herd of walkers headed for the prison?