The most challenging maps for you.

You can actually skip recruiting anyone else and just use Azure and Sniper units, using the force field to safely eliminate the enemy Azure units.

I initially thought the same, BUT:
I had an idea to cast antimagic on the snipers and then use the force field to eliminate the Azure units... but there are a few nuances: 1) The AI figures out to use mass dispel, removing all spells (including antimagic and the force field).
2) The snipers run out of shots because there's no wagon, and it will end badly...
3) If the Salamander Azure units move before ours, you'll have to fight all over again...