I also have a unicorn type splitter, brand forgotten. It was set up on a roller stand, so that you could power it off the rear wheel of a car or truck with the other wheel on the ground. It did actually work, but it was mighty scary. There was a kill switch you were supposed to keep very handy, because if the log jammed, the vehicle could simply drive off the stand and be down the road. I've seen other versions with a flange that bolts directly to the wheel, and others that use a tractor PTO.
The splitting itself was fast and very powerful for knotty wood, but messy and splintery, making the wood rather unpleasant to handle.
I was given this rig back in the 1970's by someone who found it unfriendly to use, and quickly concurred. The remains of the thing have been languishing in my barn for many years. If i-r machinist would like to shorten the product cycle a little, let me know. the screw/cone is detached, and could be attached to some other shaft or flange. I imagine it's got a good bit of surface rust by now, but last I saw it was nice and sharp, and a pretty hefty piece of material.
But really, I'd not recommend this unless you have a supply of gnarly, knotty elm or something that nothing else can get through. It's dangerous and ergonomically unpleasant to use.