Lightsworns, known as Lightlords in Japan, are a set of monsters introduced in Light of Destruction. Their primary effect involves self-milling, sending cards from the top of your Deck to your Graveyard, either as a cost to activate their effect(s), or as part of the effect(s) itself. This may seem like a bad idea, especially since Lightsworns currently do not themselves have any way of specifically preventing this discard effect (although you could use Light-Imprisoning Mirror), but two of their most powerful monsters - "Gragonith, Lightsworn Dragon" and "Judgment Dragon" - require a good number of Lightsworn monsters in the Graveyard to be of good use, and another Lightsworn monster - "Wulf, Lightsworn Beast" - is Special Summoned when sent from the Deck to the Graveyard.
"Pot of Avarice" may help replace some of the discarded cards, reducing some of the side-effects of self-milling."Solar Recharge" and "Card of Safe Return" can add even more speed to the Deck. In the OCG and TCG, many players are using Lightsworns to counter "Dark Armed Dragon" Decks, because of their field swarming capabilities. This Deck is quite capable of a very fast OTK using their mill effects, and then summoning "Judgment Dragon", or by using "Glorious Illusion" if you have strong Lightsworns in your Graveyard. "Judgment Dragon" alone would easily be able to create an OTK situation fairly quickly.
