I've been using Ludicolo in the rain, and with Stealth Rock support, the aggressive nature of my team has been tearing through the bulkier Pokemon. I'll usually have Stealth Rock and Rain Dance in play, and with these two, Ludicolo get best most of the bulky attackers, with Kingdra waiting to clear up later on. On my standard OUish teams, I also find that spreading status round works a charm.