A curse he didn't have time to utter flitted through Eldarin's mind as he felt a sudden pushing pain from behind, causing him to stumble forward right into the following swing of the knight in front of him, barely able to bring his shield up in time to prevent the blow for bisecting him. But it still hurt and send his tripping backwards, though directed away from the knight that had initially attacked him. That heavy armour would've served him well here compared to the chainmail that had been forced to bear the brunt of the blow from behind, but there was no time for those thoughts. Now they were outnumbered and already wounded on top of it all. 

This battle had to be ended quickly, else the blood loss and numerical difference would prove fatal. Eldarin decided it was best to take care of the side knights first as it seemed they served the middle one, so he turned to face the one that had stuck him. A low growl began in his throat and Eldarin pointed his sword at its head. Merely a moment later energy crackled along his arm and burst forth from the tip of his sword in the form of lightning at the knight's head. His sword was a poor catalyst and indeed quite diluted the effects of his spell, but it was better than the severe burns that would linger in his hand if he didn't use a catalyst when casting lightning. As it was his arm was stinging and he had lines of light burnt flesh along his arm, painful but not overly debilitating.