Originally Posted by Fat col49
Hey, I know this is a work in progress, but I'd like to give my two cents because I like Mesprit and want to see it used more :] Atm, I really don't see the use for Shadow Ball and Ice Beam on the CM set. Shadow Ball is basically hitting just Psychic-types, which I feel is better achieved by Signal Beam, which in addition to hitting Psychic-types also covers Dark-types, as well as pegging Grass-types, making for a generally more extensive coverage move. Ice Beam just seems to be there be because "yada yada BoltBeam is good coverage, and doesn't really help with anything tbh (a +1 Ice Beam doesn't OHKO Druddigon, and +1 Psychic 2HKO's :[ ). I would rather run HP Ground or something of the sort, which offers a strong coverage move for Steel-types without reducing a Speed EV, while also hitting Drapion. Basically, I feel the best slashes for the set would be CM/(Psychic/Psyshock)/(Signal Beam/TBolt)/(HP Ground/Sub). Also a Life Orb mention or slash really wouldn't hurt, since it really helps Mesprit to net some crucial KO's iirc.
The SR set seems a little off to me. Ice Beam is just really meh to me, and it really just makes it susceptible to Steel-types switching in and taking advantage of it. Your stated targets of Ice Beam are all really shaky, with Mandibuzz being both uncommon and smashed by the more generally useful TBolt, Slowking not getting hurt by it at all(?), and Sandslash being not only able to only really Toxic it, but also being 2HKOed pretty safely by Psychic either way. TBolt/HP Ground seem more generally useful to me, though if I'm missing something let me know !_! Moreover, with Pokemon like Crawdaunt growing in popularity as of late, I feel it best Mesprit runs more than minimal Speed to perform at full capacity in this metagame. Personally, I've been running a spread of 144 HP / 228 SpA / 136 Spe, which allows it to outpace +Speed natured Base 55's (Crawdaunt and Omastar being the primary examples) and below with a few EV's deviated from SpA to get a Lefties #, and it's worked wonders for me. Lastly, a mention or slash of Lum Berry is definitely important if only for being able to sponge a Smeargle Spore and U-Turn out to something to KO, since it's a very relevant aspect of the metagame :< I also wouldn't say that Dark-types "counter" this set, as Mesprit is more than capable of U-Turning out on them and dealing them good damage (Absol takes 52% min. from it lol), but they do threaten it with their STAB and are capable of Pursuit trapping it.
Also, and this is really nitpicky, but Physical Choice isn't "outclassed" by Gallade and Medicham, as Levitate, mono-Psychic typing and better overall bulk give it a niche, and the use of Fire Punch flips off one of Mesprit's biggest nemeses, Escavalier, but this niche is rather small and cannot properly be taken advantage of more often than not. Also you could probably toss all the punches / Zen Heabutt into the category of "physical attacker".