This mod allows  a fully charged Unrelenting Force shout to decapitate enemies.
This can be a lore-friendly, gameplay-wise balanced addition, – or a full blown “the heads just roll” fiesta, and anything in between.

The mod is fully configurable in the mod menu. The conditions for decapitation can depend on the enemy NPC health, level compared to the player, distance from the player, random chance, and more (such as requiring a sneak attack, allowing the NPC to block the attack, etc.).
The out-of-the-box default settings were tuned for a moderately-balanced mechanic.

Full description and the rest of the informations can be found on the Nexus Mods Page.