Petrification + Sacrifice is the best, but it only works on the 2nd turn. That's the whole problem.

Here are the detailed characteristics of the Necropolis Mage, Zenda. He's a combat mage with 1 medal, and he completed the "Difficult" level against 5 "Strong" AIs in the "Broken Alliance" scenario.
Zenda, Necropolis, Master of Darkness, Level 28.
The skills are listed in approximately the chronological order in which they were acquired in the actual game.

10. Charismatic Leader 1.