Confused is a debuff which causes controls to reverse. When applied to a player, ◀ Left acts as ▲ Up and ▶ Right; ▶ Right acts as ◀ Left; ▲ Up acts as ▼ Down, and ▼ Down has no effect. See Notes for more detailed control behavior. When applied to enemies, a question mark appears above them, and causes them to move away from the player rather than towards them. Enemies with ranged attacks will be unable to use those attacks. The debuff can be prevented with the Trifold Map (and by extension, anything crafted from it), which is dropped by most enemies that cause the debuff.
About 70% of enemies and the entirety of bosses in Terraria are immune to the Confused debuff. Many of the vulnerable enemies include slimes, bats, and most fighters.
Using regular wings: the player can fly normally, but with inverted horizontal controls.
Using wings with vertical boost (e.g. Jetpack): the boost can be activated by holding ◀ Left and ↷ Jump at the same time.
Using wings with hover ability (e.g. Hoverboard): the hover can be activated by holding/clicking ▲ Up while flying, depending on the Hover Controls setting.
Using flying mounts (e.g. UFO(Desktop, Console and Mobile versions), and Lava Shark(Desktop, Console and Mobile versions) in liquids): ◀ Left makes the player ascend to upper-right; ▶ Right makes the player go left; ▲ Up makes the player descend; ↷ Jump makes the player ascend; ▼ Down has no effect.