Get Death Cards:
Get Berserker - Complete Breaking Point.
Get Body Armor - Complete Ring of Steel.
Get Cold Dead Hands - Complete Vendetta.
Get Flak Jacket - Complete Relentless.
Get Hard Headed - Complete Little Resistance.
Get Painkiller - Complete Blowtorch and Corkscrew.
Get Paintball - Complete Heart of the Reich.
Get Sticks and Stones - Complete Their Land, Their Blood.
Get Suicide King - Complete Hard Landing.
Get Thunder - Complete Semper Fi.
Get Undead Soldier - Complete Eviction.
Get Vampire - Complete Burn Em Out.
Get Victory - Complete Downfall.
You Will not get Death Cards if you only complete the missions, first you have to find it, then you must collect it.