The Undead creatures soon realize they're hunting a soulless thing and thus in their astonishment, I assimilate them into my own mana and construct a mercurial frost battalion that unleashes a blizzard storm on the hill. Everything in its path is either killed or frozen in thick unmelting ice that will take even a century for the impossibly strongest person to break out (yes, even Chuck Norris or any ridiculous summoned creature). While you wait out for the ice to be broken, I fortify the hill with a blood-construct - Andromeda Galactical Atelier of Fantome. MY HILL.