Sacrificial Pit – how to use it correctly?

Diplomacy can be used to gain Empathy, which is beneficial for a Warlock-Chaos Knight, and the effect is noticeable. So, I wouldn't rule out the possibility of leveling up Diplomacy for Kifri.

With a town level of 1, Kifri is slow to start. Therefore, she is only chosen for medium to long games or against opponents where Chaos is not effective. In this situation, I level up her combat skills and also invest in Summoning. In such a scenario, the aura of speed is more useful than Empathy.

If I'm going for a Chaos or rush build, I choose completely different heroes.