"This wasn't me at my best. Twenty-two mages killed hundreds of people, if not thousands, in one battle. Thirteen of them died, compared to over thirty thousand soldiers. Sodden." Istredd wasn't there, but it haunted him for a long time because of Yennefer.

"I could probably do better than a few animals. I know magic that would snap dozens of necks with one flick of my hand, easy. But ...." Istredd sighs, folding his arms against his chest, looking at the dead beast. "I've never had to kill anyone. I was always sheltered in my tombs and books."

It's more about potential than practice. Istredd's been trained to kill, there should be no doubt about that considering how at ease he just was in it. It's easy to imagine how it would be if he wanted to, and maybe that's why he is so hesitant. Even in the Pit he was more focused on keeping the peace and finding a way out. He never really tried to fight the acolytes or suggested they push it. He didn't let out the shrine monster. Istredd doesn't know if he has it in him, so far he's proven he doesn't.

Istredd raises an eyebrow at him. "If I say no are you going to make me?" They teach them to kill and seduce and control. Squeamish 'servant' things not so much.