How did Nidhogg lost

[Tint]

It's simple math [MAY CONTAIN SPOILERS ABOUT NIDHOGG]:

Warrior of Light VS Nidhogg + Eye: We win (the VS works like a = in this weird math case)
Warrior of Light VS Nidhogg + (Eye x 2): He would have double the power (since he's "half of himself" without one of his eyes)

Warrior of Light + Eye VS Nidhogg + (Eye x 2): This is the tricky part, you have to put one of his eyes to make the math look like the first example:
Resolution:
(Warrior of Light + Eye)/Eye VS Nidhogg + Eye: Eye/Eye = 0, so the Eye we had countered his extra Eye.

In the end:
Warrior of Light VS Nidhogg + Eye: We win.

And THAT is how he lost. My math is totally logical. No contest.

we already had an eye in the first fight against him so... uhm... Warrior of Light + Eye VS Nidhogg + Eye. so how did we managed Warrior of Light + Eye VS Nidhogg + (Eye x 2) in the final battle? :O