Spark Shock is Spark Man's signature weapon, originating from Mega Man 3 and reappearing in Mega Man III and Mega Man: The Wily Wars. It is featured in Mega Man Maker as of version 1.7.0.
It lets the user shoot up to 2 slow electric balls, which will stun enemies for 4 seconds while dealing a small amount of damage during that period (up to 3.96 units of damage). Shots will pass through an enemy if it's already stunned, and switching weapons will set them free. In Mega Man 3 Spark Shock only stunned most enemies and did not allow to change weapons while on effect, while in Mega Man III it allowed to change weapons. The change was presumably done to distinguish it from Ice Slasher as a stunning projectile.
Since it is an electric-based weapon, it can power Fuse Crossers and Xtenders, deactivate Fire Met Spawners, and trigger Spring Man's electromagnetism.