Cool team man!
So you've identified Rotom-W
as a big threat once Ferrothorn is gone, but another big threat is SubCM Keldeo
. At the moment your Keldeo check is Toxic Tentracruel, also Garchomp can potentially revenge. But Keldeo has a very easy time setting up a Substitute on either Tentacruel or Politoed. From there it can reek havoc on your team. Garchomp can't can't boosted Water-type attacks in the Rain and can only hope to break the Sub and maybe do a little damage with the second dual chop, but from there Keldeo sweeps your team clean through.
Because of this I recommend replacing Moltres with Specially Defensive Celebi
. I understand that you'd like to keep Moltres so I was considering replacing Thundurus-T but the fact is that Moltres doesn't bring a whole lot to your team while its SR weakness is a serious damper, even with SubToxic Tentacruel. Specially Defensive Celebi covers Rotom-W, Keldeo, RP Landorus, and really most importantly with Baton Pass it is one of the only Keldeo counters not trapped by Tyranitars Pursuit. This is important because a smart player with both Keldeo and Tyranitar will sack Ttar to destory your Keldeo check, say Latias, even if it means losing the weather war, because your team is so weak to SubCM Keldeo. Plus with this change you can free up a spot on Ferrothorn as Celebi is a fine SR setter, because of this I suggest replacing Stealth Rock on Ferrothorn for Leech Seed
Now with this change you do become a little weaker to Volcarona but I believe you can handle it with Tentacruel and Garchomp. The most threatening would be the Rain abuser one but either way Garchomp can revenge and Volc is unlikely to switch out and get another opportunity to sweep because of its SR weakness.
Trait: Natural Cure
EVs: 252 HP / 216 SDef / 42 Spd
- Baton Pass
- Stealth Rock