Claydol @ Choice Scarf
Trait: Levitate
EVs: 88 HP / 212 SpA / 208 Spd
Modest Nature (+SpA, -Atk)
IVs: 0 Atk
-Trick
-Rapid Spin
-Psychic
-Ice Beam
A very unexpected set that can find its home on Sand stall teams. Most people know just enough about Claydol to remember that it can use Rapid Spin, but this set does so much more. He has some offensive presence (not much, but enough for his purposes), he can Trick hazard setters and stat-boosters, and he can still do an admirable job of Spinning thanks to its fair bulk and that delicious Type/Ability combo.
The Speed EVs allow it to outspeed Base 110s while holding Scarf, most importantly so I can nab a surprise Gengar kill. The EVs also allows it to outspeed 0-4 Speed Base 100s after Tricking, though the only remotely killable target that hangs around this mark is defensive Celebi. If she isn't a concern, feel free to reduce the Speed investment to 192 EVs; you still beat Base 110s while Scarfed, and you can transfer the EVs to HP for added bulkiness. The SpA EVs give it just enough power to hit what it needs to, and the leftover EVs go to bulk. The 0 Atk IV is just nitpicking, minimizing confusion damage should I encounter a Swagger user.
Some example calcs against Pokes that often give Sand stall trouble:
Psychic vs. 4 HP / 0 SpD Breloom: 119.08 - 140.45% -- guaranteed OHKO (easy revenge kill or lead match-up kill, nobody sees it coming)
Psychic vs. 4 HP / 0 SpD Gengar: 100.76 - 119.08% -- guaranteed OHKO (again, surprise Scarf, I can even live a Shadow Ball from a Scarf set if need be)
Psychic vs. 4 HP / 0 SpD Cloyster: 79.75 - 94.21% -- guaranteed OHKO after Stealth Rock (no Shell Smash for you)
Psychic vs. 72 HP / 0 SpD Venusaur: 64.57 - 77.11% -- guaranteed 2HKO (a win even in Sun if you nail him on the switch with SR up; you can take ONE Giga Drain)
Psychic vs. 56 HP / 0 SpD Kyurem-B: 27.65 - 32.83% -- 99.76% chance to 3HKO after Stealth Rock (at the very least, he can't keep a Sub up)
Psychic vs. 248 HP / 0 SpD Tentacruel in Rain: 48.48 - 57.85% -- 98.05% chance to 2HKO after Stealth Rock and Rain Dish
Ice Beam vs. 244 HP / 0 SpD Gliscor: 104.54 - 123.86% -- guaranteed OHKO
Ice Beam vs. 248 HP / 0 SpD Landorus-T: 92.38 - 109.18% -- guaranteed OHKO after Stealth Rock
Ice Beam vs. 252 HP / 236+ SpD Celebi: 26.23 - 31.18% -- 31.42% chance to 3HKO after Stealth Rock and Sand (only killable if significantly weakened)
Ice Beam vs. 60 HP / 0 SpD Celebi: 41.01 - 48.31% -- 98.44% chance to 2HKO after Stealth Rock and Sand
A lot of these calcs assume you're either revenge killing or the opponent switches into you, but that's part of the point; as a gimmick, the opponent should fall into a false sense of security and assume this guy isn't a threat. Again, most people expect Claydol to simply be a defensive Spinner, and this set takes full advantage of that assumption to score surprise kills or cripple important opponent team members.