Vesuvianite landed atop him and, spikes or not, the thing was heavy. Abaddon was thickset and strong, but even with adrenaline roiling through him, he didn't know if he could even push up with the beast on his back. He tried--an attempt to shove up a little, legs shaking with the strain, and to fight.

The "fight" consisted of bucking, and even that might've been a strong term: instead of a wildly flailing, flinging bull able to throw his enemy flying away, Abaddon was more "violently stumbling" with Vesuvianite's weight. But he was stumbling, at least.

Maybe the spikes would help.

The bull became aware of two things at once: first, that the heavy weight on his back was now gone and second, he had no idea where it had gone. He thought he heard the faintest voice, a word maybe, or two, but he was so busy thrashing around in the dust that the direction it had come from was lost to him.

He reacted on instinct, reflexively kicking out in first one direction and then a slightly different one, as if that thirty degrees or whatever of coverage would help. Maybe he'd get lucky. It wasn't even intended to really harm, just... following that "bucking bull" theme, he didn't want the Giant Monster Bird Lizard Thing to jump back on his back, where he couldn't get at it again!