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Unlike most Zelda games, in Four Swords you can only carry one secondary item at a time. Picking up another forces you to drop the second.

Name	description
Four Sword	A basic sword.
Hylian Shield	Deflects most attacks.
Bombs	Press to light, press again to throw; press once more to detonate early
Boomerang	Pretty basic. Stuns enemies, and always returns to you.
Magnetic Gloves	Use on magnetic blocks or other players. Stopping and using them again reverses the polarity.
Gnat Hat	Shrinks you to tiny size. Use it again to return to normal.
Roc's Cape	Press to jump. Press at the height of the jump to glide.
Pegasus Boots	Makes you run faster. You can also climb slippery slopes.