This didn't start out as a fiend deck, it was really the deck i started playing with when the game first came out.This is a result of the deck evolving to counter the mainstream decks in my area wich are mostly setup for the traditional format.The fiends first came into the deck when people started using  three man-eater bugs in thier deck. I added three La Jynn mystical jenie of the lamp and two Dark Ruler Ha Des as soon as Dark Ruler came out.When i was able to I replaced the La Jynns with Archfiend soldiers and added two Dark Necrofears and a Jinzo and the rest of the deck came from this base.

    This decks first purpose is to negate monster effects like those of man-eater bug and old vindictive magian wich can stop high powerd monsters in thier tracks at a very low cost.Dark Ruler gives the rest of the fiends in this deck(wich is all but two monsters at this time) the power to stop these effects when they atk. the oposing defense monster.This stratagy falters when confronted with very highpowered monsters so the Dark Necrofears provide a sort of wall to stop stronger monsters because when they are destroyed the act like a snach-steal and take controll of that monster("If you can't beat them make them join you.") turning the tables on your opponet.The Necrofear also has the ablity to come out of nowere if there are 3 fiends in the graveyard.To put fiends in the graveyard i like to ues cards like card destruction and gracfull charity. If you combine the card destruction  with the Protector of the Sanctuary you can wipe out you opponents entire hand and they dont draw anything.The Jinzo may not be a fiend but trap cars are a menice.

    the only real weakness of this deck seems to be when a light deck pulls out all its critical cards at the same time otherwise ive almost never lost a match.drawing all magic cards in the begining of the game dont help ethier.

Monsters:

sac:1xJinzo,2xDark Ruler Ha Des

Special summon:2x Dark Necrofear

Regular monters:

3xSlate Warrior,3xArchfiend soldier,3xNewdoria, Mask of darkness,Yata-garasu, Night Assailant,Protector of the Sanctuary, Goblin elite attack force ,Wall of Illusion, magian of faith

Magic:

Mystical space typhoon, Mage power, Card destuction , Snatch-Steal, Monter reborn, Heavy storm , Harpies Feather Duster, Dark Hole ,pot of greed, Change of Hart, Graceful Charity , Raigeki

Traps:

Call of the haunted, Karma cut, Magic Cylinder, Mirror Force, 2x sakuretsu armor, imperial order, 2x bottomless trap hole

the side deck keeps changing so im not gonna list it