I'm looking at building a rain team for VGC 2018. Is rain capable of being a top-tier strategy? What are its weaknesses besides hard Trick Room? I was told that Politoed + Ludicolo + Tapu Lele + Metagross was a good rain core. Any suggestions on what to put in the remaining 2 slots? If I didn't already have 2 Psychic-types, I'd say Trick Room Cresselia to reverse TR if my opponent gets it off, so I may want something else that can do that. Skill Swap would be nice too, for resetting Drizzle or even Psychic Terrain. Thanks!