Introduces what is easily my favorite planet, and a completely new story of nearly identical length.
New characters, new tools, new mechanics, new puzzles. Same feel (except narratively its a bit more spoopy). It's like a selfquel.
(Also, worth noting that if you start a new game, you can just go straight to playing the DLC content without having to replay or complete the base game)
If you know that you frighten easily and don't react well to it - like maybe you went in a haunted house ride once and then couldn't sleep for a week, this might not be your jam and that's OK.
It's not a skill issue, the game has been conceived so that if you scare easily but keep playing you can work around the issue and succeed. But obviously if after that initial moment of terror you just can't face playing any more that's not a good purchase.
Still spooky atmosphere for sure.