Underhell is a Half Life 2 Modification developed by Mxthe in collaboration with We Create Stuff.
Underhell Prologue requires a Source Engine game to run, and Source SDK Base 2006 installed.
Underhell Chapter 1 will require a Source Engine game to run, and Source SDK Base 2007 installed.
Ballistic Shields are Randomized Bodygroups, just like the Riot Shield, but this one resists bullets.
(Thanks for the feedback on the RiotShield)