I was going to retort with a wall of calcs, then I noticed that Technician wasn't applied for some reason.
252+ Atk Life Orb Technician Scizor Aerial Ace vs. 252 HP / 252+ Def Amoonguss: 252-299 (58.3 - 69.2%) -- guaranteed 2HKO after Black Sludge recovery
+2 252+ Atk Life Orb Technician Scizor Aerial Ace vs. 252 HP / 252+ Def Amoonguss: 504-595 (116.6 - 137.7%) -- guaranteed OHKO
252+ Atk Life Orb Technician Scizor Bug Bite vs. 252 HP / 252+ Def Amoonguss: 188-224 (43.5 - 51.8%) -- guaranteed 3HKO after Black Sludge recovery
+2 252+ Atk Life Orb Technician Scizor Bug Bite vs. 252 HP / 252+ Def Amoonguss: 378-446 (87.5 - 103.2%) -- 25% chance to OHKO
252+ Atk Life Orb Technician Scizor Aerial Ace vs. 252 HP / 240+ Def Mega Venusaur: 177-211 (48.6 - 57.9%) -- 96.1% chance to 2HKO
+2 252+ Atk Life Orb Technician Scizor Aerial Ace vs. 252 HP / 240+ Def Mega Venusaur: 354-416 (97.2 - 114.2%) -- 81.3% chance to OHKO
252+ Atk Life Orb Technician Scizor Bug Bite vs. 252 HP / 240+ Def Mega Venusaur: 133-157 (36.5 - 43.1%) -- guaranteed 3HKO
+2 252+ Atk Life Orb Technician Scizor Bug Bite vs. 252 HP / 240+ Def Mega Venusaur: 265-312 (72.8 - 85.7%) -- guaranteed 2HKO
252+ Atk Life Orb Technician Scizor Aerial Ace vs. 0 HP / 0 Def Keldeo: 307-361 (95 - 111.7%) -- 68.8% chance to OHKO (guaranteed after Stealth Rock)
It also REALLY helps with Chesnaught. You can KO even if Jolly, but it's a stupidly small chance.
252 Atk Life Orb Technician Scizor Aerial Ace vs. 252 HP / 252+ Def Chesnaught: 322-380 (84.7 - 100%) -- 6.3% chance to OHKO (37.5% after Stealth Rock)
Watch out for Offensive Mega Venu, since it might have HP Fire and will outspeed if you don't have Jolly.
Yh chesnaught is another bonus also, I knew that I forgot something. I haven't seen too many fast venus, but it helps to be cautious I guess.