Tails has one of the best recoveries in the game, as his extra jumps allow him a lot more range and flexibility in his methods for returning to the stage. His Energy Ball allows him to fire energy balls that have infinite range and can be fired in three different directions (forwards, upwards, and downwards in the air), giving him strong stage control, versatile zoning abilities and a strong edgeguard. He has some of the best instant-KO attacks in the game, including aforementioned up/down energy balls, the only projectiles with instant-KO properties in the game, as well as Rhythm Twister, one of the few instant-KO attacks that is not mapped to an up/down move.
However, he is not the strongest or most durable character in the game. He lacks the ability to cancel his momentum in the air, making him vulnerable to getting KO'd by moves that lack instant KO properties, like Knuckles' rock. His Electron Cannon has a slow firing rate, making it difficult to challenge another projectile user directly.
Regardless, his pros greatly overlook his cons, putting him in the high tier.
Uses the Rhythm Twister to spin around and strikes opponents with his tails. For some reason, Tails visually turns back on the direction he was facing when he initiates the attack, only to face the correct direction once the attack ends.