Treat it like a Berry pokemon. BFS + speed boosts are optimal.
Speed boosts are generally better than skill boosts, but heavy skill focus also works.
Max main skill level is required. No exceptions.
BFS technically not mandatory, but emphatically recommended.
Sceptile is quite possibly the most mathematically bizarre pokemon in the game. It has the 2nd lowest ingredient rate at 10.6%, while also having the 3rd fastest speed in the game. This combination produces a ton of berries, despite Sceptile being a Skill specialist.
Additionally, it has the 4th lowest skill rate at 3.52% (barely beating the legendary beasts), which means it's heavily influenced by the Pity Proc mechanic. Read more about the mechanic in the Advanced section of How to use this calculator. This means that skill triggers are worth less and speed triggers are worth more.
So, the ideal Sceptile is generally BFS with as many speed boosts as you can find. Skill trigger boosts are also helpful but they have a smaller impact pound-for-pound. For example, BFS+HSM produces as much strength as BFS+STM+STS.
How to use this calculator to assess your Sceptile
This website cannot show you the relative strength of combined specialities. Use RaenonX or Neroli's Lab to assess your overall strength, then find the closest equivalent using a combination of only BFS+speed boosts. Once you have that, plug those subskills into the calculator to measure berry output. The result is the odds of you finding one better (using only speed boosts) than your current.
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