Spooky Scythe is a Demon Set, it provides a boost to the SPD of all Demon type creatures.
Spooky Scythe I - Demon +2 SPD:
Spooky Scythe II - Demon +4 SPD:
Spooky Scythe III - Demon +6 SPD:
Spooky Scythe IV - Demon +16 SPD:
Spooky Scythe V - Demon +10 SPD: