Battle of Vodin

The Battle of Vodin was brutal, it was between the Covenant and the UNSC in the year 2532. The battle lasted for about 2 days, Initially the Convenant infiltrated the colony with a stealth ship for reconnaissance to make way for the larger invasion.

It took the Covenant a few days to find out the central hub of the colony and the cracks in the defences, after that process the stealth force started assassinating military targets to cut off communications to the outside. Luckily the undercover troops stationed on the Vodin colony had a secret radio station underground.

So when the main UNSC navy stationed nearby arrived at the planet they immediately sent down 2 battalions down to the ground. Unfortunately the SPARTAN-II Randall-037 fell from one of the planet's skyhooks and was supposedly killed, when really he crash landed into the ocean and after the battle the surviving colonists revived him and eventually settled in and married one of the colonists.

Anyway long story short the battle was apparently so brutal that a marine was pinned upside down on a ceiling  with Covenant symbols on his body and was decapitated. Vodin suffered severe damage but was still habitable, even if the colonists were trapped for 10 years on the planet without UNSC support.