As a verb, it refers to the act of completely destroying something, to "go megamanspikes" on something would annihilate it or otherwise excessively destroy it, but with the requirement of the user of the word suffering from this.
To megamanspike something is to screw up and cause massive damage, or such. Something megamanspiked isn't recoverable. Said thing can be physical or abstract. It could be a chance at a lifelong relationship, or the supports of your house.
The term refers to the spikes in the Mega Man series of video games, notable for being an immediate instant kill on contact.
I tried to ask this girl out, but she went megamanspikes and immediately told me off before I could say anything.
I tried to reattach the small piece to the ship in a bottle, but I megamanspiked and smashed the whole thing.