I think anyone who was listening to metal in the early 1990s will agree that it was the gateway album that brought them from more mainstream stuff like Metallica and Megadeth and the more extreme stuff like Cannibal Corpse.
10/18 - King Diamond
10/24 - Pallbearer
11/01 - Suffocation
11/30 - Devin Townsend
12/06 - Distant Worlds: the Music of Final Fantasy