This is my exact post in the starmie thread - but since it's now a ghost town, I didn't want to let my set go to waste. It's hard to use, but just read through it:
Starmie is a great pokemon. Its amazing Speed, and respectable base 100 Special Attack. Like most pokemon with this combination, he suffers from four move syndrome. And after suffering this, suffers from having to exchange one of those moves for Rapid Spin. However, Starmie has plenty of different niches in the OU metagame. Of course, starmie does have noticable flaws. Firstly, its defenses are absolutely pathetic. No matter how much one invests in defenses, it will never be worth it. It also suffers from 4, very common weaknesses.
This is a set that I don't believe has been mentioned yet, and I think it is much better as an anti-lead:
Starmie
Item: Choice Scarf
Nature: Timid
Ability: Analytic
EVs: 248 HP, 32 Def, 4 Spa, 220 Spd
- Trick
- Scald
- Recover
- Rapid Spin
This set is basically a varient of the bulky rapid spin - same EVs, and almost same build. However, this set is a lead, especially against skarmory, a big OU lead. Typically, you would want to start by tricking the choice scarf to skarmory/any other OU lead, and then rapid spin whatever hazards they have already set up. This fucks them over for the rest of the match, and making it easier to be clean of hazards. Starmie needs 220 Speed EVs and a Timid nature to outspeed a max speed Latias and max speed gengar. Scald is a great move for this set, as starmie with 4 spatk is 237 SpAtk, and in the scenario the lead wants to switch back in with choice scarf to get a dumb revenge kill, Starmie should usually outlive it and get an analytic boosted scald. Recover is great if starmie gets a burn off with scald, but still is a reliable for recovery.
Here are some calcs to show how you are safe against a leads offensive moves:
0 Atk Skarmory Brave Bird vs. 248 HP / 32 Def Starmie: 118-141 (36.5 - 43.6%) -- guaranteed 3HKO
You can recover that away.
4 Atk Hippowdon Earthquake vs. 248 HP / 32 Def Starmie: 132-156 (40.8 - 48.2%) -- 6.3% chance to 2HKO after sandstorm damage
252+ Atk Mold Breaker Excadrill Earthquake vs. 248 HP / 32 Def Starmie: 204-240 (63.1 - 74.3%) -- guaranteed 2HKO
I think this disproves and proves my points - I mentioned earlier that starmie is much too frail, but I also mentioned that this set would negate potential OHKOs.