Baton Pass like you guys are talking about isn't really a Baton Pass team at all. Pure BP has the following structure:
- Scolipede to pass Speed boosts so teammates can outrun things whilst they boost, making things a lot easier.
- Mr. Mime because it's immune to Roar, Perish Song, and Dragon Tail, and can create setup opportunities w/ CM vs. Dragons thanks to Encore.
- Pick 1: Mawile, Smeargle, or Mega Scizor -- the former and latter as Defense passers, or Smeargle as an Ingrain passer (usually Mega Scizor)
- Zapdos or Sylveon as a Special Defense passer (with Charge or CM) and back-up way to handle Roar (Zapdos). Also can attack (TBolt or Hyper Voice), which is nice. Sylveon handles Megazard Y better than anything else (that's the reason you would want to use it).
- Vaporeon as a Defense passer, and has Wish to keep teammates in the chain healthy (espec. from hazards), and can attack with Scald
- Espeon to clean house with Stored Power + Dazzling Gleam
This is a perfectly viable playstyle. BP isn't that easy to work with. It's all about assessing power level. How many boosts do you need for Espeon to clean with Stored Power? When should you pass? Should you keep boosting? Should you pass? However, a well-played BP team can destroy bar untimely hax and Haze.
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The other thing that's good is Scolipede quick pass (w/ SD and Speed Boosts to pass). Pairing that with a strong physically offensive teammate that's slow, such as Crawdaunt, or anything along those lines, is excellent and can work wonders.