pratyanīkam - an enemy; manyamānāḥ - thinking; balabhadram - Lord Balarāma; ca - also; mohitāḥ - confused; hantum - to kill; kṛta-dhiyaḥ - having made up their minds; rājan - O King Parīkṣit; āpannāḥ - they set upon Him; ātatāyinaḥ - wielding weapons.

In their confused state, O King, they also mistook Lord Balarāma for an enemy. Weapons in hand, they ran toward Him with the intention of killing Him.