0254 Sceptile

Bullet is preferable over Fury Cutter for its faster energy gains and greater STAB damage output. 

Leaf Blade is one of the best charge moves in the game, and with a very low 35 energy cost, along with STAB, is pretty much mandatory for Sceptile. Unlike other Grass-type starters, Sceptile doesn't "need" Frenzy Plant, but it does provide a harder-hitting option. The rest of Sceptile's charge moves are optional to provide coverage, with most of them being viable depending on the format and your playstyle. Earthquake is a very powerful move that provides wide coverage, though 65 energy can be a bit expensive. Aerial Ace is a lackluster move even against Fighting-types (Leaf Blade still has a higher DPE), but does have a niche against other Grass-types. 

Sceptile is one of many Grass-type contenders in Great League. With an offensive stat distribution and somewhat vulnerable mono-Grass-typing, Sceptile is one of the more fragile and riskier picks. What Sceptile does have to offer is the fastest Leaf Blade in the game (tied with Farfetch'd), which lets it pressure shields a bit sooner than any other Grass-type. Access to Frenzy Plant is a nice addition that gives it some extra power, but this doesn't really distinguish Sceptile from its competitors. The lack of bulk is notable however, and if Leaf Blade is taken out of the equation then Sceptile looks more like a squishier Meganium. Overall, not a terrific top-tier pick, though its access to Earthquake and Aerial Ace does give it some coverage in some niche situations. 

The prevalence of Swampert thanks to its Community Day gives Grass-types some relevancy in Ultra League, and Sceptile is no exception. Since a single 35 energy Leaf Blade is approximately a one-shot (depending on IVs), and Sceptile has the fastest access to it, there is some incentive to bring the forest Pokemon on the roster. Earthquake gives meaningful coverage against the numerous Steel-types in this meta as well, though not enough to deal with Giratina. Overall still a niche pick, but its rating will drop if Swampert isn't involved. 

With a max CP of 2757, Sceptile severely lacks the stats needed to do well in Master League. While it can still get wins against Swampert, Groudon, and Kyogre, the lack of stats really holds it back from winning most other fights. Consider other Pokemon instead.