Icicle

Icicles are objects used for traversing stages in the Sonic the Hedgehog series.

Overview
Icicles are objects that appear in winter themed stages. They are grabbable objects that the player can use to traverse through the stage. However, these icicles can not be held onto for long due to their slipperiness and fragile nature.

Sonic Adventure & Sonic Adventure DX: Director's Cut
In Sonic Adventure in it's advanced port, icicles appear in Ice Cap. When the player jumps towards them, Sonic /Tails will instantly grab onto them. From there, it is possible to move the characters around the icicle. The player can also jump off from one icicle to the next, allowing them to traverse the stage. If the player holds on for too long, however, the character will fall off due to the icicle being slippery.

Sonic Rush Adventure
In Sonic Rush Adventure, icicles appear in Blizzard Peaks. This time around, when the player grabs ahold of them, they will rapidly slide down the icicle at a very fast rate until they reach the end and fall. It is, however, possible to jump of the icicle before reaching the bottom.

Sonic Unleashed
In Sonic Unleashed, icicles are only usable by the Werehog , with said objects only appearing in Cool Edge’s night stage. Unlike previous appearances, the icicles must be grabbed manually. When the Werehog holds on to it, he can move around in a manner similar to Sonic Adventure. If the player stays on the icicle too long, it will fall down, and the Werehog will fall into a bottomless pit.