तदा then, पर्वतोपमाः mountain like forms, राक्षसाः Rakshasa, गुर्वीभिः heavy, गदाभिः maces, प्रासैःखडगैः darts, swords, परश्वधैः axes, घोरान्frightening, वानरान् Vanaras, निर्जघ्नुः struck

Then the mountainlike forms of Rakshasas attacked the Vanaras with heavy maces, darts, swords, and axes in frightening ways.