Intro:
I haven't watched the Cardfight!! Vanguard: Link Joker series since the beginning of the school year, and had to catch up from the time Aichi and the rest of Miyaji Academy arrive at their campsite while Takuto and Kai end up "Reversing" almost the population of Earth. Thanks to Thanksgiving Break, I was eventually able to see not only the new "Reverse" cards in action, but what other supports each deck had since Set 12. What caught my eye the most was the episode between Reversed Korin and Kamui (Spoilers ahead for the next few sentences). When Kamui had the finishing attack thanks to his "Strongest Beast Deity, Ethics Buster Extreme", Korin activated her only in-hand "Summoning Jewel Knight, Gloria" to win the game. Aichi later uses "Sword Formation Liberator, Igraine" to defend himself, a card with a similar skill. The effect, dubbed the "Quintet Wall" (will be called QW from this point forward) by both Korin and Aichi, seemed amazing from watching the anime. This is what it reads (NOTE: The effect is unconfirmed, and written from what is shown in the anime):

Unit: Normal
Grade: 1
Attack: 6000
Shield: 0
Critical: 1

[CONT]: Sentinel (You may only have up to four cards with "[CONT]: Sentinel" in a deck)
[AUTO]:[Counter Blast (1)] When this unit is placed on (GC), if you have a «Clan Name» vanguard, you may pay the cost. If you do, look at up to five cards from the top of your deck, search for up to five «Clan Name» from among them, call them to (GC), and shuffle your deck.

Sounds impressive on paper, too if you ask me. A card that lets you summon other Guardians from the deck with no card cost except a simple Counterblast. So I'm going to go over the basics of the card itself, and what are the pros and cons of running these types of cards.

Sentinel:
First to note is that this card is a "Sentinel", which means you can only run cards with this errata in a series of 4. Just like the "Perfect Guards" (PG), QW's are also limited by the "Sentinel" ruling. Thus, the number of QW's are limited by the amount of PG's you also have in your deck. (Ex. 4 PG, 0 QW; 3 PG, 1 QW; or 0 PG, 4 QW; etc.) So having a pull of QW's in your clan (if each clan were to have a QW) lets your deck gain a number of options. How many QW should I run to PG? Is a Counterblast and 5 milled cards or a discarded card a better cost for me in the long run? If my PG's have been too cloggy, will my QW's be insufficient? These will be answered in a variety of options, so I will take you to what I believe are the advantages of the QW.

Advantages:
There are no extra cards needed - Unlike the PG which forces a discard from your hand, the QW doesn't take away any card advantage whatsoever. The PG cannot be used by itself, but a QW can run freely by itself, and heck, may be used as a bluff in real life. I can see players bluffing the QW in the future, scaring the opponent with one card in hand. The cost of 1 Counterblast is just overall way too simple to resist.
Deck thinner - We all know that in almost every TCG/CCG, the more ways a deck can thin out, the more the chances of drawing the cards you need increase. Especially in a game like Cardfight!! Vanguard that keeps taking cards from your deck, you basically increase your chances of drawing the right cards by at least 10%, assuming you don't discard them to the Drop Zone with the cost itself.
Some decks take advantage of the QW effect itself - When I first read the cost of the skill, I knew decks like Granblue or even Musketeers would benefit from the increased Drop Zone. I also know that Angel Feather's "Battle Cupid, Nociel" and Dark Irregulars's "Dark Soul Conductor" can take advantage of its skill being placed in the Guardian Zone (GC) by chance, as Cardfight!! Vanguard is a TCG that does not acknowledge "Chains and Timing" like other games. Units like Oracle Think Tank's "CEO Amaterasu" can make use of a complete stack of units ready to assemble for a strong QW defense. Even if another QW or a PG is summoned by a QW, their effects may also be used for being placed in the correct Circle if their costs are still available. My favorite part is that this card can easily be used in Dual Clans, as long as at least a few cards from the top 5 cards in the deck could be used to defend a unit, as long as the clan is the same as the Vanguard's.

Include other guardians - If you want to make an absolute defense and are ready to finish the game in your next turn, then you can still include interceptors in the front row and guardians from your hand without them being a waste. This is different than including guardians when you activate a PG, as the PG would already do all the work.

Disadvantages:
Risky Gamble - The top 5 cards that are picked from the deck may not be sufficient shield for high attacks. They could consist of a couple of Grade 3's or simple 5000 shields that may not be strong enough to defend large attacks. You may also lose vital triggers or other units that could be game changers in the long run.

Clogged up hands - Just like the PG, the QW could also clog up your hand if you're not too careful. How? I always feel that there may be scenarios where all you have are QW's and not much triggers in hand to defend yourself in simple attacks that only need 5000 or 10000 shield to defend. Since a QW is an overall powerful card, it could be a waste to use them in the early game like a PG.

Missing the cost - A Counterblast is really simple, but only God knows how many players miscalculate the number of face-up damage in the Damage Zone (myself included). Also keeping 1 damage open lets the opponent know you're preparing for a QW to activate, and they may play around it. Be wary of this, my friends.

RISK, RISK, RISK!! - I don't know if this would be an official ruling, but I'm willing to bring this out if the Anime skill stands with what is written in real life: Once the top 5 cards are chosen and placed in the GC and you are done Guarding WITHOUT activating other GC skills like extra QW's, then your opponent can apply Drive Check, and you cannot call anymore Guardians. Like any other Guard Step in Battle Phase, you still could risk the opponent Drive Checking into triggers that may render your defense useless.

Conclusion:
The QW is a great card, and may be a huge metagame changer when Set 14 releases in Japan. But it's not a necessary "staple" like having 4 Heal triggers or a Forerunner as a starting Vanguard. PG's are definitely more absolute as they can block ANY number, but QW is for sure more cost friendly in card advantage. The QW is also a great solution to players that wish to run dual clan decks that are in need of stronger defense, yet they can crumble to players who cannot let their cards fall to waste easily and deck out. The QW is overall a player preference as others would either love the concept or hate it. Test it out now if you plan to use it. Any questions or comments? Feel free to message me.

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