And does Tailwind have any additional side effects besides doubling speed? (Pokemon Online made it sound like there was, but the listing here doesn't say anything about it)
No. Tailwind has no more effects than that All Speed boosting moves: Acupressure Agility Ancient Power Automotize Dragon Dance Flame Charge Gear Shift Geomancy Ominous Wind Quiver Dance Rock Polish Shell Smash Silver Wind and Psych Up
Update: The following moves boost speed and weren’t included on the first list •Aura Wheel •Max Airstream The following Z-Moves boost speed: •Sing •Supersonic •Sleep Powder •String Shot •Hypnosis •Lovely Kiss •Scary Face •Lock-On •Sandstorm •Safegaurd •Encore •Rain Dance •Sunny Day •Hail •Trick •Role Play •Recycle •Yawn •Skill Swap •Snatch •Grass Whistle •Gastro Acid •Me First •Power Swap •Guard Swap •Worry Seed •Switcheroo •Guard Split •Power Split •After You •Ally Switch •Quash •Bestow •Sticky Web •Toxic Thread •Speed Swap •Aurora Veil The following Z-Moves boost all stats including speed: •Conversion •Sketch •Trick-Or-Treat •Forest’s Curse •Geomancy •Happy Hour •Electric Terrain •Celebrate •Hold Hands •Purify
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