I arrived at the end of Black Mesa and I want play for the update with the World Xen, is expected to finalize when?
When it’s ready.
The team is under an internal agreement to not disclose any information regarding Xen.
The next release will be able to be purchased on Steam thanks to Greenlight, but that build will not include Xen. That is farther along in the future.
Also friendly tip: try using the forum search feature because these guys will not hesitate to rip your skull off and eat your brain if they see a new poster ask a question that has been answered a thousand (probably a lot more) times.
You know, we have a wiki and General FAQ which will help answer most of your questions. It’s a huge resource to find the most recent information on the mod’s development. Also, multiple threads about Xen have been posted. Do a search before asking questions in the future so that we’re not continually duplicating posts.