The battle wasn't all that unpredictable in Teja's eyes. The weaker gears were picked off early, leaving the battle-hardened ones to fight. Teja flicked the ichor off his sword from one beast before running the next one through with a growl. The beasts were still lurching and running through the portal that glowed just outside the protective barrier between the castle and the rest of the world. Taking a moment to catch his breath before grabbing a beast's face with one hand and jamming the sword into its neck with the other, Teja realized that he'd only put up a spell for higher demons. Lesser ones were getting through because he couldn't care less about them at the time. That, and he still wasn't sure that Dethklok wasn't some strange lesser form of evil, with all that they'd done.
He smiled faintly when Gaz started thinking with her newfound powers, and raised the dead. Good girl. Use what you've got. He hacked the arm off a monster that was lunging for him and ran his sword through to its heart.