CREATIVITY: 2.5 / 5
Zygarde-10%, while quite a trending Pokemon, still remains one of the uncommon Pokemon in the UU metagame, and with Grassium Z Volcanion being an icing on the cake as one of the unorthodox options, your team warrants a rather average score in this criterion.
ESSENCE: 4 / 5
You truly captured the essence of the secret ingredients by virtue of Mamoswine, Zygarde-10%, and Volcanion breaking almost every wall you find. What holds back to getting up a notch in this criterion is the fact that Scizor isn't exactly a reliable win condition as it fails to find a way in dealing with Stall archetypes (what more if you'd place Eeyore's Virizion instead, no?).
EFFECTIVENESS: 6.5 / 10
For an offensive team like this, you can't afford to have your momentum lost by virtue of Tentacruel; Starmie would have been more welcoming as a Spinner for this team as Toxic Spikes isn't really as needed as it looks to be, and exerting more offensive pressure is more valuable for this team. Reflective from the Essence criterion too, your team lacks a more reliable win condition as Scizor isn't dealing with Stall archetypes any time soon - Virizion could have been a great boon over Scizor; while you might lose a form of priority, Mamoswine's Ice Shard and Zygarde-10%'s Extreme Speed is more than enough to close out any offensive Pokemon that would stand against your team. Regardless, your team stands out to be weak to Mega Manectric and other Electric-types as your team lacks a prompt answer to such Pokemon. Regardless, it's still a solid effort on your part to build this nice team; good job!
TOTAL: 13 / 20