Autofocus video AND Slow Motion -- one package

<p>For years I have been an amateur wildlife photographer shooting stills. I'm interested in now also doing video work with wildlife. The main issue seems to be autofocus in video. In the stills world, trying to photograph a leopard chase or birds in flight would be exceedingly difficult using manual focus. Today's modern DSLRs do a fantastic job of predictive autofocus and the number of keepers with erratic wildlife shots can be quite high. <br>

I would love to be able to capture some of these same images in 4K video. I would need the same longer zooms/prime lenses as for still images but now there is the need to attach them to a video camera or a body that shoots both stills and video. There is also the need to quickly and accurately focus. Autofocus in the video world seems to be considered an unnecessary/shunned feature in the camera. In reviewing the available cameras, both mirrorless and dslr, I can't find even a short list of candidates. Oh, I would like to add slow-motion to the video capability since it adds such an interesting viewing addition for video.<br>

Any thoughts of a short-list of candidates that:</p>

<ul>

<li>Perform native 4K video</li>

<li>Autofocus fast moving subjects</li>

<li>Have telephoto lenses at least 400mm (and still autofocus in the video mode)</li>

<li>Perform 120fps or faster slow motion</li>

</ul>

<p>I had looked at the Sony A7Rii but no 400mm emount and adapted lenses don't do fast lock-on autofocus<br>

I had looked at the Samsung NX-1, but no lens longer than 200mm<br>

I had looked at the Canon C100M2, but no slow motion at all.<br>

I looked at the Sony FS700 video camera, but autofocus is very poor even with phase detect adapters like LA-EA2.<br>

Thoughts?</p>