The Double-Edge Sword Technique is the foundation of one of the most successful Six Samurai deck strategies. Although at first glance, it may seem prohibitively costly, clever use of the D-EST can propel you to victory.
Using the D-EST is fairly straightforward: simple choose two Six Samurai from your Graveyard and Special Summon them. These newly summoned monsters can be used to attack, as tribute, or for other more devious purposes. At the end of the turn, the two monsters are destroyed and you take Life Point damage equal to their combined ATK.
Ouch, you say. Not worth it, you say. Just wait!
Strategies and game play:
Double-Edge Sword Technique, when used by itself, is severely limited in its strategies. If you've managed to clear the field, you could use it to summon enough ATK power to land a killing blow on your opponent's Life Points. However, if the Samurai attack is countered, you will take a lot of damage at the end of the turn.
What, then, makes D-EST such a useful card for Six Samurai decks? I have two words for you: XYZ monsters. When you use the two Six Samurai monsters summoned from the Graveyard as XYZ materials, they cease to be monsters, and therefore are not subject to D-EST's effect at the end of the turn. In other words, if I summon two level 4 Six Samurai monsters, I can use them to Special Summon a rank 4 XYZ monster. Then, my two Six Samurai monsters won't be destroyed at the end of the turn, and I won't take the massive LP damage from D-EST's effect.
Are you beginning to see the possibilities?
Another useful strategy involves the built-in ability of many Six Samurai monsters: "If this card would be destroyed, you can destroy another face-up 'Six Samurai' monster you control instead." Therefore, if you summon two Six Samurai monsters with that effect, and you already have two Six Samurai monsters on the field, you can choose to destroy the two that were already there instead of the two that you summoned with D-EST. You still lose two monsters at the end of the turn, but you won't take the Life Point damage from D-EST.
Double-Edged Sword Technique is beginning to look pretty useful, isn't it?
Combos with other cards:
There are a host of XYZ monsters that you can play with D-EST, as long as your Graveyard is stocked with the right Six Samurai monsters. I'll give you a few examples, to get you started.
Heroic Champion - Excalibur: Summon two level 4 Six Samurai monsters from the Graveyard, attack with them, then bring in Excalibur for next turn. If you get him a clear shot at your enemy's Life Points, then BAM! Four thousand damage.
Shadow of the Six Samurai - Shien: High attack and an ability that boosts other Six Samurai? Yes, please.
Photon Papilloperative: Get those pesky wall monsters out of the way!
Number 30: Acid Golem of Destruction: Use this one only for a finishing blow; he's extremely dangerous to keep around for too long.
Wind-Up Zenmaines: Useful for defending your Life Points and taking out some of your opponent's cards.
Other useful combos include Spirit of the Six Samurai, which can be used to protect the Samurai you summon from being destroyed by the effect of D-EST or Hand of the Six Samurai, who can sacrifice the summoned Samurai to destroy enemy monsters (and let you avoid paying the LP cost of D-EST). The Six Samurai cards have a lot of synergy with each other, so the possibilities are almost endless!
Ways to counteract it:
Double-Edged Sword Technique can be shut down in a few ways. Monsters like Fossil Dyna Pachycephalo and Archlord Kristya, who shut down Special Summons, can be absolutely deadly to a Six Samurai deck. Because most of the Six Samurai monsters have only mid-range attack at best, powerful monsters could protect you from the monsters summoned by D-EST. Finally, cards like Seven Tools of the Bandit or Royal Decree are useful against any Trap card.
When used well, Double-Edged Sword Technique can quickly fill up the field with Six Samurai monsters, which can be used to attack, activate effects, or summon XYZ monsters. Special Summons are always handy to tip the balance in your favor.
Unless you have cards that complement D-EST, it can be far too costly to make it useful. It can also be negated by the usual array of counter-traps. Use at your own risk.
Artwork and aesthetics:
The artwork depicts Kamon and Yariza, two of the Six Samurai, emerging from a cave, ready for battle. Floating in the background is the clan symbol found on many of the Six Samurai cards. All-in-all, a good-looking card, especially for those who like the artwork of the Six Samurai.