Earth, Level 6, [Machine/Effect]
ATK: 2200, DEF: 2000
DL4-001, Super Rare (Duelist League Promo)
"Increase the ATK of this card by 100 points for each face-up Machine-Type monster on the field."
As promised earlier during Fusion/Ritual support week, here is a review of Machine King, the promo for Duelist League 4. Frankly, I don't know how you even get ahold of these cards normally. I think maybe they're won and/or bought at official mall tournament tour stops, but those never come within 300 miles of here apparently... I got my copy at Wal-Mart for a respectable $4, subtracting the price of the Labyrinth of Nightmare booster with which it came that netted me Summoner of Illusions and another Destiny Board piece which I didn't expect to see. All in all, a very good buy. I'd like to see Wal-Mart put more promo cards into packs like those; it's way cheaper than the price-gouging I've seen at card shops.
Anyways, back to the review. Machine King is currently one of the best Level 6 tribute monsters for Machine decks. He is rather similar to Insect Queen, giving himself an ATK boost so that he always comes into play as a 2300 ATK monster. He benefits from having Machines on the field, so this is ripe for exploitation via DNA Surgery. Don't have enough Machines? Make everything a Machine, and he'll power up through the roof. He pairs well in a deck with the infamous Jinzo, too.
There's another great card that Machine King can exploit which Insect Queen cannot, and that card is Limiter Removal, the old spell that is still a staple in Machine decks. It doubles all your Machines' ATK points for a turn, but destroys them all at the End Phase. Combined with Machine King's ATK increasing effect, this can put a 5000+ ATK monster on your side of the field. This is very lethal if used recursively.
Machine King isn't quite as powerful and doesn't have quite as much support right now as Insect Queen, but as the various monster types seem to be filling out more and more now, and as with Insects, there are some Machines that have very good effects, I have a feeling support for this card will grow dramatically. Because of this, I give him a 7.5/10, just a little lower than Insect Queen. He's not really strong enough to play outside of a Machine deck, though, so there's no point in a general rating.