The Sonic Cannon is an ability that appears in the Sonic the Hedgehog comic series and its spin-offs published by Archie Comics. It is the Dark Arm Power of Rhygenta, one of the four remaining Dark Arms.
The Sonic Cannon is a powerful Dark Arm Power that allows the individual to blast multiple soundwaves. These soundwaves are powerful enough to subdue at least two individuals with one shot.
Eclipse the Darkling used the Sonic Cannon Dark Arm Power when Knuckles the Echidna had the alien on the ground. Pleading for Rhygenta not to interfere with the battle, Eclipse forcefully used the Sonic Cannon to subdue Knuckles and Shadow the Hedgehog.