I catch the great white sharks, put the sword back together, put it in the center of Mars, and destroy Mars with nuclear bombs that I stole from Keg Runners.

i rebuild mars and the sword and toss the real lost sword in to a pile a stuff that looks like lost sword in the center of the earth then when u find it teleports to mars without ya

Destroy mars and run away to be an eitc captain on a juggernaut.

I hang you for being a traitor and destroy all swords in existence (Excepting my trusty Iron Blade, of course).

I grab your iron blade, and take it to a forensic lab where cops find out it's really the lost sword, then I have a dance party with the sword. My sword.

i rebuild the lost sword and it gets stuck to my hand

I chop off your hand and take it with me. I then throw the sword (with hand) into a fire, and destroy both eternally.

I take the sword, KO Keeper, and walk away with a evil grin on me face...

I take a bite out of muffin and take the sword.

I grab it from your hand. Mine.

I ban everyone with my ban bayonet... I take the sword.

I eat the rest of Muffin (Yum), and bring back El Patron. He then revokes the curse, rendering it powerless, and takes it to Davy Jones' Locker, where he casts it into Orodruin, the Mountain of Fire.

I wear a fire protection suit and take the sword and melt it into a dagger!

I break off the zipper to your fire suit so you can not get out of it, grab the dagger, run so fast you can not catch me (because you are in that awkward firesuit) - Melt down the dagger and refire into the sword. Turn myself into a ghost and vanish, sword and all, onto another plane of existance where I am crowned king of the pirates because of my magical sword :)

You couldn't forge a dagger into a sword, as you'd be short of metal. But didn't you read the above post? Even if you got it back, it wouldn't be any better than your average blade. Furthermore, I go to the dimension, challenge your rule as king, win, and seal the dimension off.