Splatterhouse

There are a few ways to get enemy heads. The demons with the tentacle arm can be killed with a Splatterkill, giving you their head as a weapon. Using the machete can net you the heads of a few enemies too. You can also use Tackle Pack from the Sprint/Roll upgrade group. Hold the RT and press the B button to tackle an enemy to the ground, and press Y while they are on the ground. Their head may fly off, allowing you to use it as a weapon. If you have Tear you to Pieces, you can also perform Stretchin' Necks by pressing B to grapple the enemy and then holding B until you perform the move. Power Head Throw from the Weapons upgrade group is helpful as well towards this achievement.