Aiming for the large open spot filled with a lot of relatively soft muscle instead of hard armor and dragonling skin had left Ackster's head, neck, and back open for Tararat's retaliation. So, when Ackster committed to the strike, Tararat pulled out his dagger and instantly aimed for Ackster's spine.
He wouldn't die. That much Tararat was confident of. But since Ackster had talked about Kargas coming to the Land of Dragons and bringing it down while also mentioning having found something in the Alchemaze, Tararat had to bring him to the elders and get the truth and details.
So, Tararat was still reluctant to go for Ackster's neck or head.
Ackster, on the other hand, had no fear. In fact, he was counting on Tararat attacking him so that he wouldn't notice Ackster amping up the power in his strike.