It's not a DC rip-off of Marvel Zombies. It came out fourteen years later, for a start, while in addition it's not subverting anything and it only has a little black comedy, here and there. It's a straightforward hero-focused zombie apocalypse in which lots of heroes die, only a tiny minority survive and the ending is upbeat, but only once you've allowed for the probable violent death of everyone in the world.
It's not too bad, though. I enjoyed it. I read all the sequels and enjoyed them too.
Unlike Marvel Zombies, there's an explanation for this plague. Darkseid tries tweaking his Anti-Life Equation. This ends badly for him and even worse for the planet Earth, but not before Darkseid's had a fun evil bit. "Remove his tongue."
Surprising choices are made regarding who lives and who dies. An extremely unexpected hero is one of the first to go down and you'll get to see lots of big DC names go zombie. Technically, mind you, they're not zombies. They've been taken over by something that's both an equation and a virus. (Eh?) You can catch it from the internet and from smartphones. (Oddly, the series started shortly after COVID-19 became a global pandemic and suddenly internet working became one of the world's most important weapons against infection. Great timing for a presumably unintended technophobic message.) We're also told that you can catch it from infected blood, yet there are plenty of instances of heroes getting thoroughly gore-splattered in zombie battles and yet still being okay. Presumably it needs blood-mingling or something.
In practice, though... yeah, zombies.
Batman and Superman both get to be cool. John Constantine, of all people, makes a glorious appearance. "Can eat a giant bag of bollocks. The world isn't over until I say it is." (He then fails to participate in subsequent events, making me wonder if there was an editing hiccup or if this is going to get followed up in a sequel. On closer examination, it looks as if his appearance was actually a spin-off comic, "A Good Day to Die", that got quietly included in my DCeased graphic collection.)
Occasionally, it's funny. Sometimes it's black humour and sometimes it isn't. "I could be a planetary threat if I wanted." "Of course you could, dear."
This wasn't the first zombie apocalypse DC-wide crossover, incidentally. There's also Blackest Night, by Geoff Johns in 2009. I'm going to guess this is better, though. DCeased is fine. Most of what it's doing is fairly obvious, to be honest, but it's hard to mess up something like this. You don't even have to be clever. Blood death death megakill bravery touching farewell, etc. This is a good, solid series that hits all its story beats well and manages to be emotional, scary and apocalyptically bleak... and yet not depressing. The (few) survivors escape and the story will continue. If you include the sequels, it's pretty epic.