Sonic & Knuckles/Controls

Tails
To fly, keep pressing to go up and stop pressing it to go down. Tails can only fly for a short time before getting tired and falling back to the ground. In addition to that, if playing with two players, player two can use Tails to fly and player one can jump onto Tails to be lifted.

Swimming is done the same way as flying, except you need to be underwater. While underwater, jump and when off the ground jump again. Tails can only swim for a short time before getting tired and falling back to the ground. Sonic may grab onto Tails, but unlike flying, Tails cannot lift him higher. Tails can swim out of water, at which point he will start to fly.