It's also missing levitate, so it's vulnerable to spikes and t-spikes, unlike Missy.Dusknoir doesn't really seem that impressive to me. It's a lot slower so it's more vulnerable to status, it can't heal status like Misdreavus so Toxic will wear it down eventually, and it can't boost. Its main advantages are probably Leftovers, Shadow Sneak and Earthquake.
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Alright, I've got a question that's been bouncing around my mind for a while. What if there existed a parallel to the Flame Orb and Toxic Orb which caused paralysis?
Like the other status orbs, I imagine it would be exclusively seen on status sweepers (I suppose that Limber Lopunny could also use it with switcheroo, but eh). Obviously, it'd be horrible for Swellow, who relies on its fantastic speed tier to function, but what about Ursaring? Ursaring actually has respectable bulk, and without toxic/flame orb eating away at it, it could gain a lot more longevity. It might see use on bulky Guts sets, as long as the user is alright with being outsped by Munchlax. What's interesting, though, is that Quick Feet negates the speed drop from paralysis, meaning that you'd end up with a sweeper capable of outspeeding Timid/Jolly Charizard, while still packing 130 base attack and a 140 bp STAB move- all without having to lose a non-negligible portion of your health every turn. The downside of this, of course, is that there'd still be the ever present risk of full paralysis, which would necessarily happen at the worst of all possible times.