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The Palm in general was recommended by alexwolf as a better way to handle Ferrothorn since it takes nothing from Mach Punch and providing Breloom with a stronger STAB fightng move.
It actually doesnt matter for its hp to be odd b/c lefties will never be a proper whole number and if running magic guard rocks dont matter at all. Also 12 spe evs gives Clefable the ability to outspeed. Just a small useful tidbit
I think for Unaware+Leftovers, you can also try a set of Calm Mind/Moonlight/Moonblast/Heal Bell. With the same EV spread as MG you still would be able to use Venusaur as setup bait but also have a mon that can check setup sweepers over having another coverage move in Flamethrower.