HAVOK tactical nuclear weapon
From Halopedia, the Halo wiki
Template:FactOrFiction Template:Explosives List The HAVOK nuclear warhead is mainly used in missiles fired by UNSC Bombers or Cruisers. However, an alternate use is to simply place the warhead on a ground target and detonate it with a remote. Its yield is thirty megatons.
Around July of 2552 during the battle of Sigma Octanus IV, Blue Team detonated a HAVOK nuclear warhead at the city of Cote D'Azur.