Chaos Control
From Sonic Retro
Chaos Control is an ability that allows the user to use the Chaos Emeralds to warp time and space. It can be used to teleport, to slow down or stop time, to travel through time, and to jump across dimensions. Chaos Control also powers many energy based attacks, such as Chaos Spear, Chaos Blast. At least one Chaos Emerald is necessary to induce Chaos Control and it is amplified with every Emerald added to its use until reaching full power with all seven.
Chaos Control was first used in Sonic Adventure 2, during Shadow's meeting with Sonic. The second time was to (very reluctantly) save Rouge the Bat from the Prison Island base, third was in Sonic and Shadow's final duel and fourth was to save the world form the collision of Space Colony ARK.
Four characters are confirmed to have the ability to use Chaos Control. Shadow the Hedgehog was the first seen to use it, and it has since become his signature technique. Sonic can also use Chaos Control, first inducing it with a fake Chaos Emerald to save his life, although he uses the ability reluctantly and only when necessary. In Sonic Heroes, Metal Sonic used Chaos Control to stop time during the final battle with Super Sonic, an ability he gained as a result of copying Sonic's and Shadow's life data. Silver opened a portal to the past using Chaos Control during a fight with Shadow in a brash attempt to use the technique against him. Finally, Lancelot's Soul Surge is very similar to Chaos Control, although no emeralds are required.
In Sonic Heroes, Chaos Control's time-freezing ability is Shadow's component of Team Dark's Team Blast, "Chaos Inferno".
In Sonic Battle, all of Shadow's attacks involve Chaos Control in some form or another.
In Sonic X, Chaos Control initially teleports Sonic and his friends to a modern equivalent of Earth, while later in the series it also takes Angel Island and other lifeforms from Sonic's world.
In Shadow the Hedgehog, Shadow can use Chaos Control after he builds up his "Hero" meter to its maximum (by destroying Black Arms troops and, in some of the levels they appear in, Eggman's robots). In this context, Chaos Control allows Shadow to automatically fly through the level until the ability is canceled or the Hero meter is emptied. Another ability is Chaos Blast, which requires a full "Dark" meter to be filled (by destroying scenery, attacking G.U.N. troops, and destroying Eggman's robots in levels where he is the Hero ally); when activated, Shadow sends out a sphere of energy in all directions, destroying every NPC and small scenery element caught in the vicinity.
In Sonic Chronicles: The Dark Brotherhood, Shadow's basic attack and all of his 'solo' POW moves involve one or more forms of Chaos Control.