From Generation V onwards, due to the way Trick Room affects Speed calculation, Pokémon with 1809 or more Speed will still act before Pokémon slower than 1809, even in Trick Room.
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If you ignore natures, items, abilities, and speed modifiers like paralysis, then a level 100 Regieleki with perfect IVs and +6 speed stages needs at least 68 speed EVs to reach that number.
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