The line "DON'T LOOK INTO THE DEATH STAR, OR YOU WILL DIE." is a reference to the manga Hokuto no Ken. In the manga, if two warriors engaged in a fight see the Star of Death, one of them will die soon. This reference was lost in the English translation, as Hokuto no Ken was not popular in America.
Dracula's grave reads "1431-76." This is a reference to Vlad Tepes (Vlad the Impaler), a major inspiration for Bram Stoker's original Dracula character. Vlad Tepes was born in 1431 and died in 1476.