Dragapult: This may just be personal preference, but I think U-turn would work well in place of Thunderbolt for pivoting. The current set you have is fine though, if you'd like to keep it the way it is.
Rillaboom is good.
Excadrill: Earthquake is never a good thing when you pair it with Grassy Terrain (halved power). You should replace it with High Horsepower, which is only a very small trade-off in power for an added benefit of not being weakened in Grassy Terrain.
Toxapex and Volcarona are good.
Mandibuzz is also very good. I'd suggest just picking either Foul Play or Knock Off, as Mandibuzz also appreciates pivoting in U-turn. Don't really see the point of Leftovers when you could use Heavy Duty Boots to avoid Stealth Rock damage, you already have good recovery in Roost. If you are iffy on Mandibuzz, I'd suggest Hawlucha as another option, as you have a Rillaboom that can setup Grassy Terrain for Hawlucha.
Hawlucha @ Grassy Seed
Ability: Unburden
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Swords Dance
- Acrobatics
- Close Combat
- Taunt
A defense boost will help Hawlucha set up easier. Acrobatics will do double damage when the Grassy Seed is consumed, Close Combat is good STAB that can't miss, and Taunt can stop some forms of status and Haze.
Hope this helped!
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