Called when the entity is about to be removed.
Clientside behaviour remarks
This hook may be called at odd times (when entity has actually not yet been removed from the server). This happens during fullupdate with the ENTITY:Initialize function not being called even when the entity reappears. You can debug this behaviour by enabling cheats and running cl_fullupdate on the client.
Please note that this information may not be fully correct and may change in the future.