Whenever a Vehicle you control enters, draw a card if it has flying. Otherwise, put a flying counter on it.
Tails is a UW Vehicles deck that floods the board with artifact Vehicles, granting flying counters (and evasion) or drawing cards as they enter. You ramp into Vehicles, crew them efficiently with cheap creatures and tokens, and beat down through the air. Flash on Tails lets you hold up interaction and deploy him as a surprise blocker or instant-speed threat.
Built-in card advantage and evasion engine—every Vehicle either replaces itself or gains flying
Flash gives flexibility, letting you play around removal and crew/block at instant speed
UW has elite control tools, counterspells, and board wipes to protect your fragile crew
Vehicles dodge most creature-targeted removal and sorcery-speed sweepers when uncrewed
Vehicles need crew, so you're vulnerable to creature wipes that strip your pilots
Tails dies to spot removal, slowing your draw/counter engine
Low base power in colors—UW lacks reach for explosive ramp or big finishers