Actually, Volcanion isn't really all that consistent, it's volatile. The deck is unpredictable so it can either draw very hot, not at all or somewhere in between. This really depends on your deck choice but you have options out there. If you don't need to run a specialized Stadium card for your deck, then you can run three or four Silent Lab, which will hurt the deck, since it turns off their damage output. Volcanion decks are known for running between zero and three Stadium cards so if you can win a Stadium war and keep a Silent Lab in play, then you should be good.
Another option you can use is to run Alolan Muk, which turns off the Abilities of all Basic Pokemon. It means you can't use your Basic Pokemon Abilities either but you have a lasting option. I believe it only has 100 HP so its always a Lysandre away from being knockedout but it can stick. If you don't want to use any of those, then a few Hex Maniac should be the best option if you don't mind using your Supporter for the turn. I hope this helps.
