The Fundamental Theorem of Algebra states that a polynomial of degree \( n \) has exactly \( n \) roots in the complex number system, counting multiplicities.
In the given polynomial \( y = 8x^5 - 2x^4 + 6 \), the highest power of \( x \) is \( 5 \), which indicates that the degree of the polynomial is \( 5 \).
Therefore, according to the Fundamental Theorem of Algebra, this polynomial will have exactly \( 5 \) roots in the complex number system.
The answer is five roots.