A ground tracking projectile, Sol Badguy slams his Fireseal into the ground and shouts “GUN FLAME!”, unleashing an explosive flame.

The first iteration in Guilty Gear is a ground hugging fireball that travels across the stage.

This was later changed into the now iconic four flame pillars erupting from the ground but limited range in the later installments.
It also has a feint version where Sol mimics the motion but doesn't unleash it.
While in Dragon Install, it becomes a big long range (but still limited) fire projectile.

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