I didn't put too much effort into this one (especially not the predator, which I put there after the herbivore and hadn't planned to begin with), and it kept getting smudged (just look at the neck), so I had to cut it short.
Another hexapod herbivore, I would guess a distant relative of the Xenogrypas, simply looking at its front legs and overall anatomy. I thought of it as "Antlered Spiketail" or "Antlered Whiptail", but the scientific name so far is only Knoutoura - knout tail, or "knoúto" and "ourá".
It's about 3.5 meters at the shoulder (4.3 including the feathers), and 13-14 meters long. It can, as the name implies whip its tail (kind of like a Diplodocus and some other sauropods) with incredible speed and strength. It may not affect a very large predator much, but a predator its own size or smaller will get bones shattered.
I'm not certain about the "antlercrest" - it may be used the same way antlers are, or it might just be for show.
The little predator (little and little, it's 1.5 meters tall) is related to the Pugiodon. It has mobile teeth (not sure if I'll keep the big ones fused to the jaw - are they bone, like in Dunkleosteus? - because it reminds me too much of Toublodon, Cuspicanis and etcetera), and it may be venomous, I'm not sure yet. Will update this species with name and a proper drawing.