This is a great link for a break down of strategy by the Chiefs, open the link for more....
There were four of those big safeties on most plays: Tyrann Mathieu, Juan Thornhill, Daniel Sorensen and L’Jarius Sneed. It wasn’t until late in the third quarter, when Mahomes and the Chiefs had taken a commanding 31-15 lead, that Spagnuolo ultimately switched to a more aggressive three-cornerback/three-safety form of coverage designed almost exclusively to stop the pass.
https://fivethirtyeight.com/features/the-chiefs-defense-used-four-big-safeties-to-get-to-the-super-bowl/