Cletus was happy to assimilate St. Estes building into his Extrembiote, turning it into a twisted house of horrors.

Source: https://screenrant.com/venom-original-nemesis-cletus-kasady-carnage-back-extrembiote/

Kletus Casady (aka Carnage) bonded with the Extrembiote, the villain was able to mind-control denizens of the Big Apple via mobile devices, making people kill each other as his first move.

Source: https://www.cbr.com/red-goblin-normie-rascal-redeem-osborn-legacy/

Now his powers have been boosted, thanks to the Extrembiote.

Source: https://www.cbr.com/marvel-comics-symbiotes-hosts-venom-carnage/