Sabbat blew everyone out of the water when they dropped their début album on the Thrash Metal scene in 88. When Martin Walkyier's unique vocal style, intelligent lyrics, and perfect timing were paired with Andy Sneap's smorgasbord of frantic riffs something truly special was born. If you have any interest in the history of Thrash, you need to hear HoaTtC; its influence on later generations is impossible to measure. The links below sound like shit but is all I could find.
(On a personal note, the album art! Wow! It's like something GW might use, but that doesn't stop me loving it. It's one of my all-time favourite album covers.)