The Obsidian Oath

The team's structure takes after a relatively standard Bh balance, so it should be played as such. Vaporeon is usually the best as your lead / early game scout to asses how threatening opposing sets are. (This will be important later for determining where to use Leafeon's Destiny Bond as using it incorrectly will often lead to a swift loss). Flareon and Jolteon are your best way to make progress in the early game as Jolteon can remove key items and spread chip with Thunder Cage and Poison and Flareon just hits hard with miminal set-up. Once you know that Umbreon's checks are removed (usually via Flareon or Jolteon) you can go for the win with Take Heart. Vs regen-vest, Jolteon, and Vaporean are you best options for managing the chip from Mortal Spin and Salt Cure. Vaporeon is noted here is as the opposing regen-vest is a steel it can't Poison it and Vaporeon can take advantage of the opposing regenerator to heal off Salt Cure damage. The plan vs Take Heart also takes a bit of explaining: Since you often can't switch Leafeon in directly (especially if you need Destiny Bond for something else) you instead want to initially go Sylveon to absorb any hits. Then if the Take Heart Pokemon tries to set-up to break Sylveon you U-Turn in Leafeon and the lock them into Take Heart with Encore. Then you alternate Encore and Mortal Spin to chip them into range of being Koed by Flareon, Jolteon, or Vaporeon. Then on a turn when they can't attack you bring in the best of the 3 to force it out or kill it.