What's a horror movie with a number in the title?

Friday the 13th I
Friday the 13th II
Friday the 13th III
Friday the 13th IV
Friday the 13th V
Friday the 13th VI
Friday the 13th VII
Friday the 13th VIII
Friday the 13th IX
Friday the 13th X

Friday 13th

Seven

I guess you can add a whole load of sequals into this list too.

Child's Play 2, Friday 13th part 3, Halloween H2O or Scream 4, as examples.

Scream 1 2 and 3
Saw 1 2 3 4 5 6 7 8

The Omen 666 (remake)

Jennifer 8

Pi

23