I have played many puzzle-style video games over my years of video game addiction, both in single player and versus mode. While I do also think that Tetris Attack is the best puzzle game I've ever played in single player mode, it is much easier for me to explain why I consider Tetris Attack to be the best puzzle game ever created for versus games: to analyze what Nintendo did right. Furthermore, it's a slightly less contested claim- I've heard a lot more people assert that Tetris Attack is the best competitive puzzle game ever than assert that it's the best single player puzzle game ever.
Tetris Attack has simple mechanics. We'll start with the most basic considerations. Tetris Attack is a simple block-based puzzle game, in which players must clear panels from a well by aligning three or more of the same type in a line, vertical or horizontal. The only way to move tiles is by selecting two horizontally adjacent tiles with a free-moving cursor (or a tile and an open space) and to swap them; there are no vertical moves. This is the only move legal in the game. Tiles, for the most part, constantly rise from the bottom of the well, and when any reach the top of the screen you have only a short grace period to remove them before it is game over. This is simple to understand; in one paragraph, I have explained the basic rules of the game. It is easy to pick up and play quickly.
Tetris Attack has a very low luck factor relative to skill. Although the tiles rising from the bottom of the screen come in random order, and tiles created from garbage blocks are equally random (more on those later), skill overcomes luck in almost all instances, to a degree not found in most other puzzle games, because of the large number of legal moves. In Tetris, for example, a skilled player can be completely screwed by a very bad run of pieces. The same is, admittedly, true in Tetris Attack, but it is extremely uncommon because there is rarely a situation where a particular line of pieces is likely to be game-losingly bad. There is luck in occasional accidental attacks (more on those later), but a skilled player can produce them much more reliably than an enthusiastic player clearing pieces as quickly as possible with no thought towards attacks. Because the entire well can be rearranged at any time, a run of pieces that does not support the well as it stands can be used by changing the setup that already exists. In Tetris, for example, players do not have this option; a set piece remains in the well until it is part of a full line and you may just be waiting forever for that I-shaped piece. Because skill can create attacks twenty to thirty times more frequently than pure luck, and skill can almost always overcome runs of inconvenient tiles, luck plays a small role in the game.
Tetris Attack is an extremely aggressive game. As the name might imply, it is easy to attack your opponent with a frequency limited only by how quickly you can manipulate the pieces; we have already established you are not likely to be spending time waiting for "that right piece". Attacks do not rely on bonus pieces or special power-ups; instead, only a moderately special piece clear is required to throw a garbage block at your opponent. While clearing three or more pieces will remove them from your well, clearing four or more (obviously sliding the middle in last, or else the three will be taken- pieces sliding up from the bottom of the well lining up and causing a three have demolished several of my better arrangements) with one swap will simultaneously throw a garbage block on top of your opponent's well. A small garbage block, but it's a small bonus clear. More complicated manuvers- most notably, creating chain reactions where the pieces falling into the open space created by a clear cause further sets to clear- will result in larger and larger attacks, frequently in excess of the pieces you actually cleared. Garbage blocks are not terribly difficult to remove; clearing a piece on which the garbage block rests will panelize the garbage block and turn it into regular tiles, and any garbage blocks touching that one of the same color will also be panelized. But while garbage can be easy to deal with, it is very easy to create!
Very skilled play is rewarded appropriately. This is the first thing that most puzzle games with aggressive multiplayer modes are likely to fail at. Combos (getting four or more blocks with one move) and chains (when pieces fall to produce more clears) produce attacks, and the effectiveness of the attack is proportional to how diffiuclt the move is. A combo of N pieces will create a group of single-thickness garbage blocks, no more than five tiles across (they always leave space at the left or right), with total volume equal to N-1 pieces. Because these are single-thickness blocks, they are all panelized at the same time, in most circumstances. They are therefore easy to clear, and the disintegrating blocks are very likely to create chain reactions- so the attacks that are easy to create are also easy to handle. Large combos, however, create large quantities of garbage, and while it is still easy to panelize it, that garbage can push a stack over the top of the well if the player isn't ready to handle it. Chains are much more difficult to create, because the setup is more involved; it's easy to accidentally clear something you didn't mean to and wipe out all your careful planning. They are also less likely to happen by accident. The smallest possible Chain- two steps, or a x2- is not very difficult to create, and so its garbage block isn't much worse than a decent Combo. An N-step chain creates a full-width garbage block N-1 rows thick. A thick garbage block, in addition to having enough raw volume to be a definite problem, can only be cleared one layer at a time, requiring careful play- and if several thick garbage blocks are stacked atop each other, the first panelization will result in a layer of regular panels sandwiched between garbage blocks- insulating the garbage blocks from each other so they do not continue to break up when the lower level of garbage is broken. Long chains, therefore, drop extremely dangerous garbage blocks- and this is appropriate for how difficult it can be to create sufficiently long chains.
Despite this consideration, I have found that the skill involved in withstanding reasonably frequent attacks of a given strength is about equal to the skill involved in producing such attacks. The upshot to this is that while there is an aggressor's advantage, it is not so extreme as to unbalance play under huge piles of garbage from relatively simple attacks, as is known to happen in Puyo Puyo. In fact...
There is no such thing as an attack large enough to cause instant victory. Tetris Attack always gives players a grace period when their piles are at or over the top of the screen, unless playing at the highest difficulty level- and then a pile under a Stop will still survive, until the Stop expires. Even a massive garbage block off the top of the screen can still be split in layers. When a player's well is full, that player usually has a few seconds before a loss of game occurs. The grace period counts down when and only when the pile would be rising. The pile does not rise while pieces clear, so constant clears can delay the not-so-inevitable; furthermore...
Attack moves also have strong defensive properties. The only meaningful defense is extremely aggressive play. Whenever a player clears a Combo or Chain, the pile stops rising for a bit- and the grace period, if it's in effect, is also paused in its doomsday count. The time for the delay is roughly proportional to the size of the garbage block the attack throws. Therefore, a player who is already in trouble is best advised to keep attacking, rather than play some form of defense that has no effect on the opponent- a common situation in many puzzle games, resulting in monotony when a defensive player can stay alive but never threaten an aggressive player, resulting in very long games where the defensive player never gets to do interesting attacks and the aggressive player never feels pressure. Since defensive play causes attacks in proportion to how strong a defense is, a player in danger is as much of a threat as, if not more than, a player in no trouble. Furthermore, this is how there is no such thing as an insta-kill: a sequence of Chains and Combos can keep the grace period indefinitely paused, as long as the player never slips and keeps the Chains and Combos going... putting more and more garbage over in his or her opponent's well. As a direct result,
A player is never doomed. There is always room for a comeback. Because game-loss can be delayed indefinitely by the Stop from Chains and Combos- a stop which is much longer when a player has piles very near or over the top than in other situations- a player is never inherently doomed from attacks unless he or she has played poorly enough that the entire well is nothing but garbage blocks and there are no actual panels to move (a rare situation, and one in which the player deserves to lose because he or she could avert his or her fate with a few taps of whichever button raises the pile a line). And remember, anything that pauses a pile attacks the opponent- so skilled play can take a player out of danger while burying the opponent under piles and piles of garbage. And the thick garbage block that caused the problem? Well, keep in mind that
Counterattacks are possible and strong. Furthermore, the counterattack mechanic is implicit in the design and not a special rule. The second part of this is more game design elegance than a major consideration, but it is a favorable thing. When a garbage block panelizes, the panels that are created may immediately fall to create clearable groups. These groups are counted as Chains, built off of whatever clear originally broke the garbage block. Pieces float in the air for a second or two before falling, and that is enough time for a skilled player to place a matching pair under a falling garbage panel to create a counterattack chain reaction. A very skilled player can make sure that this set will define the highest level of the well- so when the panel falls, the further layers of the garbage block (if any) will fall with it, and the counterattack chain will continue when the garbage block panelizes. Devestating attacks can be created this way; my personal best is a x9. For comparison, the entire well is twelve lines high; the eight-line garbage block fills 2/3 of the entire well. (x4 is considered an impressive manuver.) This makes for very tense (and therefore fun) moments when a large garbage block gets passed back and forth between players, gaining strength every time- until somebody eventually fails to deal with it and promptly loses the game.
The game can be played competitively at any level of skill. Tetris Attack has a second kind of attack. As the game progresses, more and more Shock Panels will appear (until they are eventually as frequent as any other block); note that there are never any Shock Panels in the opening well and they are very rare in the first five lines that appear from the bottom of the screen. Garbage blocks never panelize into Shock Panels. Creating any clear with Shock Panels- even just a basic three in a row- will send a Shock Block to your opponent. A Shock Block is a garbage block equivalent in size to a x2 garbage block, but it is grey instead of whatever color you create with Chains or Combos. This has several implications. Firstly, the game is competitive even with unskilled players, because they can rely on shock panels to send attacks. The attacks are neither frequent nor impressive, but against low-level players, they are sufficient. Secondly, very talented players can use them in a carefully-timed manner, releasing a Shock Block in the middle of a sequence of Combo attacks. The Shock Block is a different color, so it splits what would be a pile of single-thickness garbage blocks into three groups (including the block itself), which must be panelized in three moves instead of one. Poor players can compete with Shock Blocks alone for a game that does not feel like two disjoint games; contrast this with classic Tetris, in which players clearing only single lines will have no effect on each other whatsoever and might as well be playing seperate single-player games. Mediocre to average players will find themselves throwing reasonably frequent combos to deal with, while skilled players will duel with thick blocks from moderate chains- and expert players will send gigantic blocks and spend most of the game frantically making chains and combos to keep the grace period timer from calling game over because the garbage blocks have stacked up far beyond the top of the screen! At any level, the game is interesting, and the attacks are a reasonable challenge for the players of that skill.
Attacks are never squandered. This is a common source of irritation in sword fighting in Puzzle Pirates: the most impressive parts of a large attack never reach an opponent due to restrictive rules of how attacks are placed, or cancelled. This does not happen in Tetris Attack. Even if a player is already over the top of the well, additional garbage blocks are cheerfully piled on top, causing a player to have to fight that much harder to get out before the end of the grace period. As previously stated, expert versus expert is usually a high-adrenaline clash of two piles well beyond the top of the screen!
Victory almost never seems "cheap". Even when a player is defeated with a gargantuan garbage block or six and there are no ways to clear pieces because there are no lines at the bottom of the screen, this type of victory is clearly a test of skill- to get that much garbage in! Games which do not end in a well entirely full of garbage and no panels are generally hard-fought affairs. The only time a victory feels "cheap" is when an opponent loses for pressing the "Raise Pile" button too many times, and this is a mistake that a player very quickly learns not to make.
The game design forces the match to reach a conclusion. Despite the rules that allow infinite chains and combos to stall death forever, the game is generally pushed to a conclusion. The pile rises at an accelerating rate throughout the match; attacks that are managable early in the game may be fatal later on because the Speed Level has increased. Furthermore, the Speed Level affects the length of the grace period and how long the pile stops for in case of Chains or Combos. The speed constantly increases throughout the game, requiring better and better play to simply remain alive. (The primary single player mode of Tetris Attack, in fact has the increasing rate of tile appearance as the only obstacle to success. It's enough.) In a game between expert players where the pile spends the vast majority of the time paused and over the top, counterattacks inherently must form- and these counterattacks tend to grow as the game progresses, as a counterattack completely removing a three-thick garbage block will generally produce an x5 chain, which produces a four-thick garbage block- and so forth, meaning that players have more and more to deal with in their chains of counterattacks, until someone eventually drops the ball.
Tetris Attack, in short, managed to avoid mistakes that plague almost every other puzzle game I have ever played. Chu Chu Rocket frequently feels "cheap" when victory is because of an unexpected last-minute cat, Puyo Puyo ends without warning in a single attack that may not even be that impressive, Tetris is dull for inexperienced players, and Meteos delivers attacks proportionate to the number of blocks cleared, which is frequently a poor metric of how difficult the attack was to produce. Tetris Attack is not on some sort of untouchable pedestal; learning from the mistakes it didn't make can be quite useful to game designers in the future hoping to create multiplayer puzzle games of a similar caliber.