Valmiki Ramayana Aranya Kanda Sarga 43 Shloka 5

राजन् O king, हृष्टाः happy, मृगयां चरन्तः while on hunting expedition, राजानः kings, कामरूपिणा assuming any form at his free will, अनेन by him, पापेन malicious, वने in the forest, उपाधिना deceitfully, निहताः killed.

Many kings, while on hunting expedition in the forest, have been deceitfully killed by malicious Maricha, who could assume any form at his free will.