Pisachas and Ganas

[Deathblob]

You can clear that province with your prophet set to banish, a bunch of archers on Fire Large Monsters (so they target the shieldless ghouls), and an infantry screen to stop the undead from getting to your prophet and archers.

[Louist]

I can have a couple priests there in 3 turns, but no sooner. While I don't have eyes directly on the other side, the lake that forms half of the chokepoint falls within my dominion, exposing the black candles on the other side. By the time I'm able to clear them out, I'll have lost my chance. Rotten luck, that! I'll just have to make do without such a choice piece of land.