Xposed Call Blocker is a call blocker implemented on the lowest common userspace level. This means that it's better than any other app at blocking calls without diverting them through the network.
Other advantages include minimal RAM usage, since there's no service continuously running in the background.
Block incoming calls on a per-number basis, or using wildcards.
Internal call log that stores which calls were blocked.
Wildcard blocking: you can now block patterns (e.g 054* to block all numbers starting with 054).
Unknown contact blocking: you can now block any number not in your contacts list.
Fixed a bug where call blocking might not work when "Toast blocked calls" is unchecked.
Separate toast options for incoming and outgoing calls, previously only incoming toasts were configurable.
Fixed long tapping items in call block history being reversed.