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The most obvious thing about the three dark types in the Sevii Islands is that they are all originally from Johto. However, another cool thing about them is they can all be found in and around caves on different islands, with Larvitar in Sevault Canyon on Seven Island, Sneasel in Icefall Cave on...
I'm fairly new to the tier, so I'm probably not too qualified to give out advice, but it seems like without a grass move on Venusaur or Ice Beam on Clefable, ground types like CB/Sash Dugtrio and RP Torterra are a major threat to your team, especially if spikes are up. I don't know how you might...