Personaly, worldslayer is one of my favorate cards for it's power to clear the board, I recently thought making a deck with worldslayer and creatures such as doomed traveler or creatures with undying in order to leave behind a little army to finish the opponent off after a hit with Worldslayer. Apart from that strategy you can also reserve creatures without undying with Oblivion Ring, once worldslayer wipes the board, your exiled creature will return unharmed.
Now I'm a somewhat crappy deck builder so I want YOU the community to help me make Worldslayer a better card for players. I've made a somewhat Mediocore start to a deck that needs all the improovement possible, if you wish to help making my pile of crap turn into a stack of gold blocks that would be awesome or if you like this idea and want to make your OWN deck and submit it to me or the comments below you are welcome to do so.
Here is a link to my crap pile if you want to mess around with it: http://www.mtgdeckbuilder.net/Decks/ViewDeck/147595
Constructive critisim helps, but please don't be a douche about it :)
I'm looking forward to see what a such a large community can do for this.
And here is a link to my decent worldslayer deck: http://www.mtgdeckbuilder.net/Decks/ViewDeck/147610