Soul Surge (ソウルサージ,Sourusāji?) is a Skill used by all playable characters in Sonic and the Black Knight. When equipped with this Skill, the characters uses the energy in their own Soul Gauge to perform a special move.
When using Soul Surge, the user performs a special attack that allows the user to either attack enemies, launching a kick to bump objects or to advance quicker through the stages in Adventure Mode. The Soul Surge's performance and effects differs between each user as it utilizes the user's special attributes and skills (Sonic's super speed, Percival/Blaze's pyrokinesis, Lancelot/Shadow's chaos powers etc.) in its performance.
To perform Soul Surge in gameplay, the player must have some energy in the Soul Gauge. To activate Soul Surge, the player must press . While active, the player is allowed to keep using the Soul Surge for as long as the player has energy in the Soul Gauge. To suspend the Soul Surge, the player must press . The energy in the Soul Gauge will decrease when Soul Surge is used, and if it runs out the move will end.
The action the player can perform with Soul Surge depends on the conditions and the player's action while the Soul Surge is active:
When there are enemies nearby when performing Soul Surge, if the player flicks the Wii Remote, the playable character will launch an offensive attack at the target/nearby enemies that can destroy weaker enemies and inflict heavy damage on tougher enemies.
When there are targets nearby when performing Soul Surge and the player swings the Nunchuck Remote, the playable character will launch a kick on the chosen target which can momentarily stun opponents and trigger reactions with certain objects.
In the Adventure Mode of Sonic and the Black Knight, when there are no enemies in range when perforning the Soul Surge and the player flicks the Wii Remote, the playable character will initiate a high-speed dash akin to Speed Break from Sonic and the Secret Rings.
For some of the Soul Surge users, a red targeting reticule appears above nearby foes when using Soul Surge in gameplay, which allows the player to select a target to attack with Soul Surge and to continue attacking with it by swinging the Wii Remote when the reticules appear over new enemies. By attacking when the reticle is bright white and the playable character's blade is glowing, the player can perform a Perfect Hit for more damage and extra points.
To use Soul Surge in gameplay, the playable character must be equipped with this Skill. Unlike most other Skills, Soul Surge is a standard Skill that will always be equipped to one of the playable characters' weapon/combat styles. However, the player first obtains Soul Surge in Adventure Mode when clearing the mission "Special Mission: Reach the blacksmith's shop" in Camelot Castle.
During the battle with the Dark Queen, Excalibur-Sonic can perform a Soul Surge where he launches a powerful combo of sword slashes with Excalibur. This is the only move that can damage the Dark Queen.
The Soul Surge used by Shadow the Hedgehog and Sir Lancelot is called Chaos Punishment. When performed, the user teleports to the nearest enemy with Chaos Control and attacks, while time appears to have stopped when attacking. If Ddraig Goch is equipped, then Lancelot attacks the enemy with Chaos Blast, destroying more enemies in the vicinity.
The Soul Surge used by Knuckles the Echidna, Sir Gawain and Sir Lamorak is called Gail Meteor. When performed, the user throws their weapon to a targeted enemy. All enemies that are in the path of the thrown weapon are also hit. If Flamberge is equipped, Gawain always targets the furthest enemy, allowing multiple enemies to be hit on the way back, while creating explosions upon impact.
The Soul Surge used by Blaze the Cat and Sir Percival is called Flames of Kilekion. When performed, the user engulfs herself in a flaming tornado and charges through enemies. If Joyeuse is equipped, Percival creates bigger and stronger fire tornadoes.
Sir Galahad's personal Soul Surge. When using this technique, Galahad produces a field of psychokinetic energy that destroy/damages any lesser enemy. Any playable character caught inside its vicinity, however slowly loses rings, and then loses twenty rings on the last hit.