Bassnium

"Currently Bassnium is the most powerful energy on Earth."

- Dr. Wily

Bassnium, known as Fortenium (フォルテニウム) in Japan, is the energy that powers Bass. It was accidentally discovered by Dr. Wily.

Characteristics
Not much are known about Bassnium. The alloy is an infinite energy source that provides incredible power output and excellent mobility. . In actual uses, the energy's appearances varied from neon green to purple. Bassnium emits an surrounding aura the arm/foot whenever it comes to close combat, or giant charged shot comparable to Bass' own height, or an aura which simply suspends him in the air. His strongest attacks have taken on the frightening shape of a skull. Despite the vastly strong and somewhat frightening power, there are no known drawbacks to the use of Bassnium energy. However, just like Mega Man, Bass's Special Weapons use regular Weapon Energy instead of the signatured Bassnium.

Backstory
After gaining numerous defeats, in hopes of creating a rivalry robot, Wily began to analyze Mega Man. During the process, Wily accidentally discovered this powerful energy which he later used in Bass's construction. It was named Bassnium.

Mega Man 2: The Power Fighters
Tired of his constant defeats, Dr. Wily began to study Mega Man hoping to create a similar robot, during this process he unintentionally created a powerful energy source which he named Bassnium, he then created Bass using this energy. At the time of the classic series, Bassnium was the most powerful energy in the world. Dr. Wily later tells Bass about his discovery of Bassnium, and how he is studying this energy to create a new powerful robot.

Trivia

 * Although revealed in The Power Fighters, Bassnium was never mentioned or having a important role in the whole rest of the series.
 * The "-ium" suffix often describes the metallic characteristics of the element. This leads to the speculation that Bassnium is some kind of metal, or radioactive metal to be more exact and specific. However, it might be used just to sounds cool, and to present the energy-like form and its enormous power, just like those radioactive matters.