Card of the Week #13: Number 66: Master Key Beetle
2 Level 4 DARK monstersOnce per turn: You can detach 1 Xyz Material from this card, then target 1 card you control, except this card; while this card is face-up on the field, that card(s) cannot be destroyed by card effects. If this face-up card on the field would be destroyed, you can send one of its targets to the Graveyard instead.
Number 66: Master Key Beetle is a powerful Xyz monster which was used by Vector in the anime, and released in Judgment of the Light. There are many reasons why Master Key Beetle is a very powerful Xyz monster, the main reason being it's effect. Once per turn, by detaching one of its Xyz Material, you can prevent one card you control, except Key Beetle itself, from being destroyed by card effects. This is an incredible effect, as it can make another boss monster you control unable to be destroyed by card effects, and even continuous Trap Cards.
Notice that Master Key Beetle doesn't specify that the card you're going to protect has to be face up? That means you can set a continuous Trap Card, then use Key Beetle's effect, protecting your Trap Card before you've even activated it. Using Key Beetle on continuous Trap Cards is a very powerful play, as the usual way to get rid of them is through destruction, while Key Beetle will make them near impossible to get rid of.
There are also two continuous Trap Cards that work great with Key Beetle: Safe Zone, and Vanity's Emptiness. If you use Key Beetle on Safe Zone, then use the same Safe Zone on your Key Beetle, then Key Beetle will be very hard to squash, as Safe Zone prevents it from being targeted by card effects, as well as destroyed by either battle or card effects, while Key Beetle is protecting Safe Zone from being destroyed by card effects. This creates a very powerful lock that most decks won't be able to find a way out of before you defeat them.
Vanity's Emptiness works great with Key Beetle, for multiple reasons. One of these being that Vanity's Emptiness prevents both players from Special Summoning, and most decks these days rely heavily on Special Summoning, so if they can't destroy it, they'll be having a very hard time. Another reason is that Vanity's Emptiness destroys itself if a card is sent from your field or Deck to the Graveyard, basically preventing you from activating cards if you want to keep it active. However, if you protect it with Key Beetle, then it won't destroy itself, so you're free to activate whatever you want, without worrying about letting your opponent Special Summon.
Unfortunately, Master Key Beetle isn't generic; it requires two level 4 DARK monsters in order to be summoned. The decks that can summon it, however, welcome it with open arms, most notably Umbrals (it's no coincedence that Vector runs Umbrals in the anime, and happens to use Master Key Beetle). Umbrals can easily summon Rank 4 Xyz monsters every turn, with Umbral Horror Ghoul, Unform, Druise the Devious Druid, and capable of recycling themselves with Recurring Nightmare.
Two other decks that make great use of Master Key Beetle are Evilswarm, and Gravekeepers. Evilswarm usually focus heavily on keeping Ophion alive, and Key Beetle makes that so much easier. Ophion also sometimes just won't cut it, as not all decks need to Special Summon level 5 or higher monsters, so if Ophion won't do you any good, Key Beetle usually will. Gravekeepers love this card, as they need to keep Necrovalley active as long as possible, but being a Field Spell, it's easy to destroy. If you protect it with Key Beetle, your fears of your opponent destroying it are all gone, and Gravekeepers Spy makes Key Beetle easy to summon.
Another great thing about Master Key Beetle is that it's a DARK monster, with 2500 Attack Points, which means you can tribute it for both Eradicator Epidemic Virus, and Deck Devastation Virus, if need be.
and seriously safe zone + Beetle is really good it ruins life and gives you a good defence till you draw good cards nuff said