Shadow Vikavolt

Shadow Vikavolt is basically the ultimate incarnation of the route-1 Bug. It stands as a contender for the gold medal among all Bug Types, and is actually a fairly strong Electric Type as well, giving it solid role compression alongside a good amount of raw power. Add to that the fact that it's arguably one of the freaking coolest looking bugs in the game, and you've got yourself a decent value. However, keep in mind that one of the roles that it fills is bug of all types, and that as an Electric Type it's competing with absolute monsters like Regieleki or Shadow Electivire. This means that it's primarily good as an early to late game investment, but falls off once you've got stronger hitters. Still, the Bug meta doesn't currently have a lot of likely room for growth right now, so it's likely to have some utility moving forward for the rare double-bug-weak raid boss.

Best PvE Offensive Moveset

• Bug Bite and X-Scissor makes Shadow Vikavolt one of the apex Bug Types in the game
• Volt Switch* slightly out-performs Spark in terms of DPS, but the difference is minor, and the latter has the advantages of being easier to dodge with and non-Elite. Whichever you pick, pair it with Discharge.
• Mud Slap and Crunch fall behind, and while Fly is an objectively amazing move that gives Shadow Vikavolt its highest neutral damage output, Shadow Vikavolt does not want to compete in the Flying meta!

Best PvE Defensive Moveset

• Shadow Vikavolt has a great moveset for defense, as most of its moves are entirely relevant and worth considering.
• Mud Slap tends to out-perform Volt Switch* a bit due to its stronger damage output and great coverage, though the latter does built energy faster and isn't that far behind thanks to STAB.
• Discharge has the highest average performance among Shadow Vikavolt's Charged Moves. However, it's best to not pair it with Volt Switch*, as a pure-Electric moveset is very easily walled on defense.
• Crunch is also worth considering due to its outstanding neutral coverage
• Fly is also worth considering despite being 2-bar due to its coverage profile and damage output.
• X-Scissor is the weakest option here due to its lower power and poor coverage, but it's not objectively bad.
• Bug Bite and Spark are weak on defense.

Volt Switch provides fast energy generation, letting Shadow Vikavolt spam its Charge Moves more often. Bug Bite is an alternative choice with a balance of average damage output and energy gains, though Bug-type damage is more niche in the meta. Mud Slap gives up energy gains in favor of stronger damage output, but lacks STAB with Vikavolt. 

X-Scissor costs the least amount of energy in the game, allowing Shadow Vikavolt to bait shields often. Discharge helps to fulfill Shadow Vikavolt's Electric-type role and is useful against common Water Pokemon. Crunch doesn't have as much value for Shadow Vikavolt, though it is an option nonetheless.