Proto-Duodoseic language

Phonology
PDuo contrary to the common sound changes of Nuclear koyanic languages, it merges Palatals and Uvular consonants into the velar /k kʰ/, the way the laryngeals only colour the vowels but do nothing else. In all other langs they have some secondary effect (kát tone, qʼač ejectives, gäj voicing), *x₂ becoming /e/ when not next to a vowel but *ɑ becoming /o/, in all other langs *x₂ and *ɑ remain associated with each other.

While in theory you could still describe this as being more closely related with some weird sound changes, it definitely seems like the most divergent language so far, so not part of the nuclear group.