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Grass/Fairy fits pretty well to Frolifaun, by evolving it grows horns and becomes a physical attacker with horn leech. Pic related
Harember should evolve into a Fire/Electric, with high Sp. Attack. Gets larger ears that work as lightning rods
Marcol is obviously a deffensive/support mon, it could stay as pure Water or become Water/Steel by having a huge spiked shell, something similar to Slowbro's tail.
I know it would be pretty unbalanced, but giving some Ground and Fighting attacks to Frolifaun could help it.