Silent Realm

The Siren World is a location in Skyward Sword. It can be accessed by thrusting Link's sword on the blue, glowing ground located in a forest area. When Link thrusts his sword, he will activate a siren power and be taken into an alternate dimension of the current world he is in. The Siren World is similar to the normal world, except it has a blue atmosphere and seems to be similar to the Twilight sections from Twilight Princess. As such, knowledge of the normal area will help Link navigate the Siren World version of it.

Overview
Since Link accesses the Siren World with the use of his sword, he will be unarmed while he explores the alternate dimension. To leave the Siren World, he will have to collect a series of tear-shaped items, resembling Tears of Light. However, collecting one of these items releases a Guardian, which is a powerful creature who inhabits the Siren World. Guardians will come after Link, and one single hit from them will defeat the young hero. Link must use the tear-shaped items in the alternate reality to stun the creatures for a limited time while he continues to look for the items. A flower on the side of the screen acts as a timer, with its petals disappearing to indicate how long the Guardian will be stunned.