There's only two Tails, but each Tails has two tails, making it four tails. See, I used the capitalization of the headline as misdirection! Just watch the video.
Old and new versions of Miles "Tails" Prowler (or M.P.H. to his friends) join Sonic and Sonic in the Gamescom trailer for Sega's generation-hopping hedgehog adventure later this year. He's been relegated to the tail end of the trailer, which I'd like to imagine is someone at Sega's trailer construction department being witty.
Either way, the real star of this trailer is the game environments, just as frantic and dizzying as they need to be, with plenty of breath-stealing drops thrown in to sweeten the pot. I'm impressed so far, though there's still time between now and the November release for Sega to give somebody a handgun.