Percentage.

Swoosh!

A spark of red light appeared from the depths of the barrel. The spark slowly became a tiny crimson ball that let out tiny currents of electricity.

''GROWL!'' The shadowy creatures were close enough for their disgusting breaths to reach Isaac's nostrils.

''Pulverizer!'' Isaac pulled the trigger and immediately lit the whole pathway in a deadly crimson hue!

Whoosh!

A crimson beam left the barrel and drilled straight through hundreds of shadowy creatures!

[Pulverizer: Using this skill, the player can unleash a powerful laser beam that annihilates everything in its path]

Isaac chose Pulverizer as his 200-level skill; even now, it was one of his strongest skills!

The crimson beam continued traveling across the pathway, killing everyone that happened to be on its path.

Burnt corpses of the shadowy monsters littered the pathways as the crimson hue slowly faded away.

Isaac opened the interface and saw his percentage rising.