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A special variant 252spattk/252spe with Hyper voice/Fire blast/Heal bell/Roost is very underrated and still hits fairly hard, as well as providing solid cleric support. Some forms of stall also run this set with a bulkier spread. As it gives mons like Blissey room to drop heal bell and provides...
Correct, the only reason for Kommo's rise in rank is due to it's new z-move. Any other sets it can run in UU are just outclassed by other mons in the tier. Without that it would most likely fall back into UR.