If it has LO or Leftovers, then I can change attacks and heal with Roost, whereas the a Choice set will be at the mercy of Stealth Rock, unless you have a spinner or something like that.
Also, for Sceptile to destroy Moltres it has to come in. Moltres's two STABs -Fire Blast and Hurricane- will OHKO Sceptile indefinitely. So the only way it can come in is on Roost or a Substitute. Sceptile can revenge KO Moltres, but that is a common weakness among many offensive Pokemon.
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