( In this AU, The Tide Changers are just Atlantis citizens and Cody isn't the king, neither is Joe. It's a completely different person. Cody is the apprentice of Pikalus while Joe is a scientist there. )

A virus broke out in Atlantis, and the few that were at the lab during the accident were changed.

Cody was among them.

Pikalus and Joe managed to escape but Cody was caught in the blast. Changing into an undead monster, he was among the horde that spread the disease.

Many months pass, and Cody misses being human. Unlike most zombies, he isn't mindless. He has a conscious.

In an attack, he spots his brother fighting among others. Joe points his pistol at him, but realises that's Cody. Pikalus realises this too as they both point their guns at him. They point them away though as another wave comes onto them.

After they take out the attackers, Cody talks to them for a while. Then someone else comes over and points his gun at Cody.

Joe and Pikalus explain quickly that Cody was good, and that he would have killed them a while ago if he wanted to. The stranger backs off, but glares at Cody.

The rest of the group have to learn to get used to having a zombie in their group, the group consists of;

Kraken
Cannibal
Joe
Pikalus
And Cody

Soon enough, Sam and Selena join.

But when Cody gets feelings for a certain kraken, he finds it hard to resist biting them after a while.

But eventually, he snaps and Joe has to hurry to find a cure, along with Pikalus.

When they do, they inject him with it and he's human again.

Kraken and Cody eventually fall in love, but the whole group eventually fall, one by one, until Cody, Joe and Kraken are the last ones left.

As Cody watches Joe get bitten, he and Kraken both get shot by a raider, and they die side by side.

...
OKAY WOW THAT GOT DARK QUICKLY