The mechanics behind the Slide are very similar to the Skid Attack, but better as it possesses greater range and speed. In order to perform the Slide, the user has to be running, or simply moving at high speeds. Once moving, the user then falls down and slides along the ground with his feet in the front, which creates a blue/yellow field around them. While sliding along the ground, the user can attack and damage any enemy or weaker obstacles caught in his path. This also allows the user to squeeze through narrow entrances or doors that is coming in at high speed. The Slide will automatically continue until the user gets hit, slows down from the Slide's friction, or goes off a ledge.
It should be noted that the Spin Dash in some games (mostly for 3D games) can be an alternative for the narrow entrance issue if one does not pick up speed for the Slide, especially since it can be done from a stationary position.
The attack range, or rather the distance and speed the user can slide, is determined by how fast he was moving before performing the Slide, as it is the force created from his speed that drives the Slide. In other words, the faster the user is running prior to the Slide, the longer range the Slide has and the more enemies the user can strike with it.
If chosen, the user can at any time break the Slide before coming to a halt, and resume his running nearly undisturbed. Therefore, in Sonic's case, if the player wants to preserve Sonic's momentum when forced to do a Slide, it is advisable to time the Slide so that Sonic only has to perform it for a fraction of a second.
Shadow the Hedgehog
Despite being a similar to Kick in Sonic Heroes, Shadow was the first to use this attack in Shadow the Hedgehog. While running, the player can tap the Action or Attack button (though only the action button can be used if Shadow is carrying a ranged firearm) to slide into foes and under tight spaces, as well as being able to curve the direction of the slide. Shadow can also jump out of the slide with a backward flip in order to reposition himself, and from there can perform a midair action such as a Jump Dash or Homing Attack.
Sonic the Hedgehog (2006)
The Slide reappeared in Sonic the Hedgehog (2006) as one of Sonic's moves. In order to perform the Slide, Sonic has to possess the Level Up ItemAntigravity. Once obtained, the player can freely perform the Slide with Sonic by holding / when moving, and can as well direct Sonic's path along the ground when sliding with the control stick for a short time. It can be stopped by either pressing the attack button or by letting it run out on its own.
Sonic also glides across the water sections in the game in the same manner as Slide, even if the player has not yet obtained Antigravity.
The Slide later returned in Sonic Unleashed as one of Sonic's standard moves. In this game, Sonic can perform the Slide by pressing / when running and break it by releasing it, but will slowly reduce Sonic's speed if continuously used. If Sonic tries to use the Slide when standing still, it will make Sonic perform the Crouch, a move where he ducks/crawls around on all fours. Sonic will crawl under tight spaces should he not be running and is instead simply standing near one.
The Slide also appeared in Sonic Colors. Its performance and mechanics are identical to Sonic Unleashed's. In this game, no matter how still Sonic stays when near a tight space, he will not crawl, but instead will always manage to slide under at a slow speed.
The Slide appeared again in Sonic Generations, where it is only used by Modern Sonic. Its performance and mechanics are identical to how they were in Sonic Unleashed, though he can, like in Sonic Colors, always perform the Slide, no matter the speed he is going at. Additionally, if Sonic runs into tight spaces he needs to slide under, he will automatically slide at a slow speed.
When Sonic and Elise are together in Sonic the Hedgehog (2006), Sonic's sliding light become golden instead of blue.