Scolipede

Scolipede's arrival in Pokemon Go caught many by surprise, though its stats and movepool aren't exactly impressive for the Pokemon Go meta. While it's not the best in either of its typing categories, it can still perform decently if you ever need a Bug or Poison attacker. 

Best PvE Offensive Moveset

• Bug Bite features the superior performance, but by a very narrow margin.
• Poison Jab trails right behind, but its typing may give it advantages depending on the opponent. 
• Sludge Bomb is recommended for its strong damage output and 2-bar efficiency.  
• X-Scissor doesn't deals as much damage but has a typing niche against Psychic and Dark Pokemon. 
• Megahorn is a step down and also slower as 1-bar move. 
• Gyro Ball has no use on offense. 

Best PvE Defensive Moveset

• Poison Jab performs better on defense due to its higher base damage. 
• Bug Bite offers slightly more useful coverage, but its damage is still inferior.
• Sludge Bomb is the most difficult to dodge, and hits quite hard as a 2-bar move. 
• X-Scissor as a 3-bar can be spammed on defense, and hurts Psychic-type attackers. 
• Megahorn is a 1-bar move, which is less likely to be used before Scolipede faints. 
• Gyro Ball is very slow on defense and easy to dodge. 

Poison Jab offers superior energy generation, but Bug Bite can still be viable if Bug-type coverage is preferable, or if the former would be resisted. 

X-Scissor costs the least amount of energy, gets STAB, and can be used frequently to either bait shields or chip away at the opponent. Sludge Bomb provides strong Poison-type coverage, hits quite hard with STAB, and costs a modest amount of energy. Megahorn is the main niche for Scolipede, as it hits very hard with STAB, and lets Scolipede stand out from other Bugs and Poison-types. Gyro Ball is a mediocre move, costs a steep amount of energy, and doesn't provide much value other than targetting Scolipede's weakness to Rock-types.