एवम् in that way, उक्तः having spoken, राक्षसेन्द्रः Rakshasa king, महोदरः Mahodara, तथाbe it so इति thus, उक्त्वा spoken, पतङ्गःmoth, पावकम् इव enters the fire, ताम् अरिसेनाम् that army of enemy, प्रविवेश entered

Having spoken like that by the king of Rakshasas, Mahodara entered the army of the enemy like a moth enters fire.