Light Speed Shoes

The Light Speed Shoes (ライトシューズ), also known as the Light Speed Dash Shoes (ライトスピードシューズ), are an upgrade available to Sonic the Hedgehog in the games Sonic Adventure, Sonic Adventure: Director's Cut, Sonic Adventure 2, Sonic Adventure 2: Battle and Sonic Unleashed.Shadow's equivalent are Air Shoes.

Description
The Light Speed Shoes' appearance differs greatly between the games, but shares the trait of being based on Sonic's footwear.

In Sonic Adventure and Sonic Adventure: DX, the Light Speed Shoes look like Sonic's Power Sneakers, but are adorned with circular attachments on the sides of the heels. In Sonic Adventure 2 and Sonic Adventure 2: Battle, the Light Speed Shoes are attachments to the heels on Sonic's Soap shoes. In Sonic Unleashed, however, they are a golden version of Sonic's Power Sneakers and are described as being made of the same material as rings. In each of these games, they allow Sonic to perform the Light Speed Dash and travel along trails of rings.

In Sonic the Hedgehog (2006), the Light Speed Shoes are replaced by the Light Chip.

Sonic Adventure
In Sonic Adventure, the Light Speed Shoes are found in the sewers in the Station Square Adventure Field after defeating the Egg Hornet boss. Head down the manhole at the road in the City Hall area. Once down there, head to the end of the sewer and the Light Speed Shoes will be at the platform to the right.

Sonic Adventure 2
In Sonic Adventure 2, the upgrade is found in the Metal Harbor stage. After the first Star Post, get over to the next platform. The Light Shoes can be found on the top of the tower on that platform, which can be reached with the pulley.

Sonic Unleashed
In Sonic Unleashed, the Light Speed Shoes can be found in Shamar's Entrance Stage, on a cliff to the left after Sonic enters the Entrance Gate and is a requirement to reach the next Day Stage. In order to obtain this upgrade, Sonic must either have obtained the Wall Jump Shoes and/or the Air Boost Shoes.

It is only found in the PS3/360 version, since Sonic already has all upgrades at the start of the game in the Wii/PS2 version.

Sonic Shuffle
In Sonic Shuffle, normal Sonic wears his regular trademark shoes but Super Sonic wears the Light Speed Shoes from Sonic Adventure. The shoes allow Super Sonic to perform the Light Speed Dash, an improvement on Sonic's Spin Dash. Sonic can perform a Spindash on the board and move twice the spaces of the original card if it was selected twice in a row (You pick a 6, then on the next turn another 6, you move 12 instead, if you picked two 5's then you move 10 and so on) but it only works once and resets. The next time you pick the same card again you move the normal amount of spaces. Super Sonic improves this by moving double the spaces for a third and fourth turn if you are lucky to get all the cards in a row.

This variation of the Light Speed Dash is different as Sonic does not use rings to move, he instead dashes without them.

Trivia

 * Though the Light Speed Shoes are treated as non-optional Upgrades in the Sonic Adventure series, there are several ways to bypass their laid-out usage in gameplay.
 * In Sonic Adventure and Sonic Adventure DX, the Light Speed Shoes, are non-optional and you cannot progress to the next level, Casinopolis, without them. But you can get out of the sewer without them by spindashing and jumping at the step with correct timing. Sonic will jump really high out of the circle dome and proceed back into Station Square. He can however not reach the button that opens the Casinopolis door, so he must go back to collect the Shoes.
 * In Sonic Adventure 2 and Sonic Adventure 2: Battle, the Light Speed Shoes are only required to complete Crazy Gadget. Though non-optional, they can be skipped up until Crazy Gadget. If Sonic were to jump onto the boxes surrounding the pulley after it has pulled him up, he can jump up onto the roof of the structure were the pulley is located. Going to the edge closest to the Shoes, charging up a Spindash and letting go will send Sonic off at high speeds, and at the other edge with perfect timing jumping will send Sonic up in the air fast enough to reach the barge that would normally be inaccessible. There is another line of rings at the end of this barge to be used to travel to the next section, but jumping down from the barge reveals a platform with a rocket allowing Sonic to get across.