Last time was the Hydreigon line, today will be about the fire moth Pokemon, Larvesta and Volcarona.
My thoughts: Even though Hydreigon is my favorite Pokemon of all time, Volcarona is my favorite Bug type, and IMO the best designed 5th Gen Pokemon. I find Volcarona almost flawless, it has a gorgeous design and is great to use in battle. That is the making of a great Pokemon. I did say almost though; Volcarona is great in that all it takes is one Quiver Dance and it's sweepville from there, but you do have to watch out for: the 4x weakness to Rock, Bravest Bird, and from my personal experiencemail, a bit of frailty. Even without the former two, I've had my Volcarona OHKO if I choose to set off a Quiver Dance. Still, 90% of the time you are going to get that QD, and then the fun starts.
Concept wise, I have to say Volcarona has one of the most creative. Before Solgaleo, Volcarona seems to be based on a combination of all manor of sun based deities. It's also based on the largest moth in the world, the Atlas moth. So to sum it all up Volcarona is a Sun god in the form of a super moth. That, is awesome.

Overall: Volcarona is a GOAT Pokemon. Again, it has a gorgeous design, and is great to use in battle.