Solution

The Battle of Bhangani (1688) was fought during the pre-Khalsa period of Guru Gobind Singh's life. It was his first major battle and occurred before the establishment of the Khalsa in 1699. This battle was fought against a coalition of hill rajas near Paonta Sahib. Guru Gobind Singh emerged victorious, demonstrating his leadership and martial skills.

The other battles listed occurred after the formation of the Khalsa:

• Battle of Chamkaur (1704): Post-Khalsa, during the Mughal resistance.
• Battle of Muktsar (1705): Post-Khalsa, involving the legendary "Chali Mukte".
• First Battle of Anandpur: Also post-Khalsa.