This is a set created by me and one of my friends named Faraway Soul. Give him all the credit, not me ^_^
Warning: This will not work nearly as well or not at all without Toxic Spikes support. This set works best with, but does not require, Spikes or Stealth Rock.
Ever hate it when you're using Kyogre and you're out of Water Spouts? And then, you're forced to Struggle and you finally realize that your spent? Well, this will make a nightmare out of that situation...
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Mewtwo @ Leftovers
Nature: Timid
Ability: Pressure
EVs: 212 Spe/ 240 /HP,/58 SpA
-Substitute
-Recover
-Ice Beam/Flamethrower/Taunt (Based on your team)
-Ice Beam/Flamethrower/Protect (Protect is recommended)
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words and math
Any reason not to use Deoxys-S or A? Both can run the exact same set unless you opt for flamethrower and have more speed. Also, it seems like Substitute/Protect/Recover/Taunt would be best, because you can abuse your speed to stall as mentioned, and also to taunt any taunters/ResTalkers/setup pokes.
Aerodactyl can run this set in OU with Roost and has an interesting option in Agility, allowing it to obtain 788 speed after one use. Weavile has Pressure, Substitute, Protect, and Taunt, but lacks a recovery move. However, it also gets agility and has the option of torment so you can keep them from spamming, say, Tackle indefinitely.
EDIT: Forsaken copied my quote editing! :D
EDIT AGAIN: It doesn't make much sense to me to only have Protect as an option instead of making it required when it makes up half of your stalling in your explanation...