Type of pair: Mixed / Other
252 HP / 4 Def / 252 SpA
96 HP / 252 SpA / 160 Spe
I know what you're thinking: "This has got to be the oddest pair I've seen in a while." And you'd be correct, it IS odd. However, it is one of the most effective Rain Dance pairs I've had. The secret lies in the type synergy that the two have, both offensively and defensively. Both are bulky, both can set up Rain Dance, and both can take advantage of Rain Dance. Seismitoad takes advantage of Rain Dance by outspeeding its opponents with Swift Swim while hitting them with STAB Hydro Pump and Earth Power. Additionally, it can set up Stealth Rock to weaken opponents up for other Rain sweepers to run through. However, Seismitoad has trouble with Grass- and Water-types, which can wall Seismitoad easily. That's where Rotom-S comes in. With Rain Dance up, it can spam Thunder to take out Water-types, while Air Slash takes care of most Grass-types, such as Amoonguss and Tangela. Additionally, Seismitoad can switch into the Rock-type moves that Rotom-S attracts. Overall, the two make a great Rain Dance pair. However, the pair does have some weaknesses, such as special walls like Lickilicky and Altaria. Thankfully, this can be compensated for by adding a physical Rain Dance sweeper like Huntail to the mix. Feel free to try this out!
I'll be day-to-day for a while, so don't panic if you don't hear from me for a couple days.