Printed close to forty times, it's been every rarity, with the exception of Ultimate Rare: it's bene a Common, a Rare, Super, Ultra, Secret and Ghost Rare so far; even a Gold Rare and Duel Terminal Parallel. Most people have tons of Mystical Space Typhoons laying around, and it's often seen as a staple. Given its reputation and its current rampant use, a big percentage of players are already pretty familiar with it, but there are always going to be people at every point on the spectrum of player skill. Even if you're on your A-game, a true master is an eternal student, and there are still players that need to learn more about MST. If you've ever been on any third-party dueling sites or applications (which can remain nameless), you've probably had someone misplay with it or think it did something completely different than what it says. It's impossible to escape popular misconceptions. Misconceptions like...Mystical Space Typhoon Negates
If you know that's true from personal experience, hit me with a few of them. Seriously.
Where does the confusion come from? Well, if you're learning the Yu-Gi-Oh! TCG as your first card game, it could be an easy assumption that "destroying" a spell or trap keeps it from doing anything. To be fair, that would be a totally logical thing to think in any real-world situation. "A thing got destroyed? Must not work anymore." It's no secret that the Yu-Gi-Oh! TCG didn't start out with a reputation for concise terminology. Wall of Illusion used to refer to monsters as "creatures." Some cards are worded plainly, and others are written in a future tense to their resolution. Fake Feather for example says "The effect of this card will be the same as the selected Normal Trap Card" as opposed to "The effect of this card becomes the effect(s) of the selected Normal Trap Card," or something similar. Problem Solving Card Text (PSCT) helps, but anyone who's tried to pick up the game fresh since PSCT got released doesn't know it's PSCT; it just looks like more inconsistency.
Then there's the idea that a face-down Mystical Space Typhoon could be activated to destroy itself when there are no other targets existed on the field. It can't, but because of hearsay and a few misunderstandings among players a long time ago, some people sure did think it could, and many probably still do. In general, no card can be activated if it can't perform its effect, and even though MST doesn't say "1 other spell or trap," spells and traps that go to the graveyard when they resolve don't affect themselves. It's the same reason Giant Trunade doesn't put itself back into your hand with the rest of the spells and traps when it resolves, and Icarus Attack can't target itself.
At face value, knowing that MST doesn't negate anything, it can seem like nothing more than a 1-for-1 backrow killer. And that's for good reason: that's what it says it is. But because Typhoon's a Quick-Play spell, it's actually much more than that when you dig deeper; chainability changes it into a hard counter to spells and traps that need to be face-up to complete their effects. All Continuous, Field and Equip spells, as well as continuous traps, need to be face-up or they won't get their effects. That means Fire Formation - Tenki won't get to search for a monster, Fiendish Chain won't stop effects or attacks from the monster it targeted, Autonomous Action Unit won't Special Summon anything, and Abyss-sphere won't bring a monster out from the deck. With Mermails and Fire Fists being the best decks of the format, and Fiendish Chain played just about everywhere, MST has a lot of power right now. Skill Drain, Call Of The Haunted, Royal Decree and Vanity's Emptiness are all popular in the competitive circuit, too, so there's no shortage of things for MST to break.
Spells and traps aren't the only thing MST busts up; you can use it to force some monster effects to miss their timing. Say your opponent Special Summons Geargiaccelerator and you have Torrential Tribute face-down, you could activate it to destroy Geargiaccelerator, but it would trigger and add something back to their hand. If you respond to the Summon with MST and chain your Torrential Tribute to that, Geargiaccelerator gets destroyed as Chain Link 2 and can't activate because its destruction wasn't the last thing to happen. What sets MST apart from similar cards in that regard is that virtually any deck can run it without conflict – there are others that some decks could use, but not many that all decks could.
Only taking MST at face value, there's still enough going on with it to consider it almost too strong. It's practically the premiere 1-for-1 in regards to backrow disruption, since it can be used proactively or reactively. When you don't need to play defensively, you can turn on the aggression and clear the way for a safe push or take the risk out of setting up a field in the early game. Other times, you can set it either as a bluff or in wait to take out an opponent's newly-set trap before it has a chance to activate. Setting it in your backrow can create a lot of mind games.
Cards that generate invisible disruption like that are always powerful, because they don't have to do anything other than exist to matter. On a higher level of play, just because MST and the art of bluffing are a part of the game, your opponent automatically has more to think about, more decisions to make, and more chances for Mistakes that you can benefit from. They already have one monster on the field: is it worth Summoning another and risking your potential Torrential Tribute or Mirror Force? That set MST could just as easily be any other card, and that's terrifying. You could create that kind of ambiguity with literally any spell or trap, but MST's equally strong, if not stronger, once it's set. You can do all of the same things you could when it was in your hand, but now you have the options to interrupt plays or break traps before they become live along with the added benefit of forcing your opponent to play around cards you might not even be playing.Weather The Competition
Fire Fists are the deck to beat this format, even if Mermails got 1st and 2nd at YCS Berlin last weekend. Fire Fists have searchability, offer huge card economy for little investment, free destruction, effect negation and swarming potential for years. They absolutely rely on Fire Formation - Tenki pulling monsters from the deck to get things rolling, and without it they're left hurting. Most of the cards that would outright negate Tenki, like Magic Jammer or Magic Drain aren't very playable, so there's generally nothing that can stop it from going through. Except MST. It doesn't need to negate Tenki to remove it as a threat. Same for Fire Formation - Tensu, which keeps the Fire Fist duelist's turn rolling longer than you'd like it to. Using Matthew Mills' Top 4 Fire Fist deck from YCS Berlin as an example, MST shuts down nine continuous spells and traps, not counting the Side Deck, on top of playing the obvious role of clearing out backrow to make plays. That means it Checkmates just under a quarter of the deck as an added bonus, beyond its usual utility.
For whatever reason, Dark World are catching on lately as a viable tournament option, and Mystical Space Typhoon sends them packing back to the bottom tables. A big part of the Dark World discard engine is cards that hang out on the field: Dark Smog and The Gates of Dark World both supply consistent and beneficial discard outlets, advancing your opponent's position in the game. Skill Drain plays a role in the deck to make Grapha, Dragon Lord of Dark World more threatening, shutting off Geargia, Fire Fists and Mermails to grind the game's tempo to a standstill. Without those cards, Dark World are basically the same hit-or-miss glass cannon we're used to seeing them as, and MST eliminates them with no external investment at any stage in the duel. Saving it for those cards instead of blowing away set backrow is way more meaningful.
After Legacy of the Valiant gave support to the Bujin, they've started making Top 8's at Regionals pretty consistently. Royal Decree's the backbone of the variation of that deck that's become popular, thanks to Stephen Mercier's build from YCS Atlanta. By removing traps from your arsenal, Bujins get to be more picky about which Bujingi get used, and you're left with a bunch of dead cards. Instead of shooting out Tenki when they search for Yamato, it's actually almost better to let them make their play, then destroy Royal Decree when it comes up, so you can keep your traps from being wasted. If you wait for your opponent to chain Decree to one of your traps, you can chain MST to push your trap through, without giving them the luxury of using Bujingi Turtle to block it. Depending on what it was Bujingi Hare could still save Yamato once, but it's a smart play overall.
There are clear and defined cards in most decks that are ideal targets for Mystical Space Typhoon; cards you don't want to deal with, that are always going to be good to have out of the way. Across the board, reserving your MST's for power cards is going to be a better game plan than shooting out backrow randomly. You've probably seen someone "blind MST," using one MST against two or three set cards, just for the sake of doing it. You might have even been the one doing it. Either way, learning not to do it and thinking critically about which cards are valuable at each stage in the game is going to lead to smarter play and generally more wins.
If you pop a backrow haphazardly without any sort of read on what it might be, just for the sake of doing it, there's a chance you'll hit a problematic trap, but then you also give your opponent the chance to set more defense afterward, before you can benefit from their one trap being gone. You might even hit their own MST and see it chained. In a game where a turn or two can make the difference, it's crucial not to waste any.A Perfect Storm
Because it's so stupidly versatile and high in utility, MST's a strong contender for the title of best backrow destruction available. It has depth of use, simplicity of text, a complete and utter lack of any requirements that might restrict your from playing it, and insane availability since it's been printed in almost every Structure Deck since the dawn of the game. Everything about it makes it timelessly good, in every deck, and it's going to keep seeing play as long as there are strong spells and traps.