Pat Stodden

A gang leader attempts to bring fallen comrades back from the dead, resulting in vampires overrunning a city.

Party house is actually portal to evil dimension, and horde of murderous beings slaughter partygoers, then homicidal children attack cars, before evildoers are all pulled back through the portal to invade another dimension.

A detective investigating a rash of mysterious drug-related deaths finds a society of Satanists bent on bringing about the End Times.