Scizor is a sweeper, preferably a choice banded one for extra power. Always use technician and adamant giving priority bullet punch team destroying powers.
If you choose not to choice band it go for a swords dance sweep that also can wreck teams.
Scizor @ Choice band
Adamant nature
252 attack,252 speed,4 hp
Technician
Bullet punch primary stab
Pursuit- coverage damages psychics on the switch
U turn - powerful stab can scout and damage psychic and dark types heavily
Brick break_ covers other steel types
for the swordance ste replace either you turn or pursuit