019 - Rattata
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Continuing our exploration of the early-game Pokemon, it's time for Rattata. Rattata is the first pure-Normal Pokemon the player will encounter and possibly one of the first Pokemon the player will catch. Such Normal Pokemon serve an important role, as they are neither advantageous nor disadvantageous against the majority of early game Pokemon. This allows the player to see how the base power of attacks work, without worrying about Type Advantage, and at the same time will demonstrate to the player how using the Type Advantage can bolster the attack power when they compare Rattata's damage output to that of their other Pokemon who are capable of scoring Super Effective Hits. If a player attempts to use Rattata against the first Gym Leader, Brock, who uses Rock Pokemon who resist Normal-type attacks, they will likely be unable to do much damage, and will realize that Type Advantage is an important part of the game that they need to learn and master if they wish to progress further.
Rattata is also the first instance of the "Regional Rodent", a small mammalian pure-Normal Pokemon who appears early in the game, and often it and its single evolution pop up quite frequently throughout the first half of the adventure. Regional Rodents aren't necessarily powerful Pokemon, they lose their luster quicker than the Early Bird Pokemon in many cases, yet they also tend to be capable of learning a wide array of important Field Moves, and thus may be kept around for that reason even if they don't see much action. As Normal-type Pokemon (for the most part), they also are somewhat of a low-risk Pokemon where Type Advantage only comes into play with Fighting, the only Pokemon that they're defensively weak to. Normal-type Pokemon can often pick up plenty of different types of moves, so even though Normal-type attacks can't hit Ghost Pokemon, and don't do much to Rock Pokemon, once the player begins obtaining TMs this becomes less of an issue. On the other hand, the Regional Rodents don't necessarily excel at inflicting Super Effective damage, so the player may opt to drop them when it's time for Gym Battles in favor of a team who specializes in taking down that Type.
Well, Rattata itself is the de facto Regional Rodent, and is simply a purplish-rat with an emphasis on its large buck-teeth which serve as its main means of offense. As a pure-Normal Type Pokemon belonging to the "realistic" category of Normal Pokemon, it doesn't suggest any elemental affiliation in its design, and like Pidgey is a creature that looks possibly like one you could perhaps encounter in real-life. It serves an important function for the franchise overall, as it helped introduce a reoccurring archetype to the series, but Rattata isn't exactly an exciting Pokemon, even among the classics it's one most people probably don't think much of.
However, Rattata has grown fairly popular in recent years due to two "memes" surrounding it. The first is the F.E.A.R. Rattata, a popular gimmick strategy in which a Level 1 Rattata, through the use Focus Sash, Endeavor, and Quick Attack, baits a high-level opponent into attacking it, lowering its HP to 1 (Focus Sash helps it survive one sure-kill attack), and then uses Endeavor which reduces the opponent's HP to 1 as well. The next turn, one hit from Quick Attack will result in the opponent's defeat. Rattata isn't the only Pokemon capable of using this, any Pokemon capable of learning Endeavor and Quick Attack are capable of it, but it's the most popular option due to how embarrassing it is for the opponent to lose to a Rattata of all things. Of course, this is a gimmick strategy, and has grown so popular that any opponent will likely know what you're attempting and easily counter it...I wonder if anyone has seriously been tricked by this strategy in real life?
The other meme surrounding Rattata is due to Youngster Joey in Heart Gold and Soul Silver (he was in the original as well, but wasn't as memorable as his remake incarnation) who constantly bragged about his Rattata being among the "top percentage" of all Rattata. There was a rumor that looking into the game's data showed that his Rattata actually was a superior specimen as it had perfect IVs (individual values, randomly generated values every Pokemon has which determines how high its base stats are) but this is actually false, and like most minor NPC Pokemon, the Rattata actually has 0 IVs. The player's Rattata is likely inherently stronger than it.
Rattata has legitimately like no presence in the show apart from having minor cameos here and there, and I don't recall an episode ever focused around it in the entire show's run---the last Johto Episode featured a bunch of them in a somewhat "important role", but I hazard to call it a focus episode for them.
020 - Raticate
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So far, all the Pokemon we've encountered have been members of three-stage evolution families, which are the most memorable part of the Pokemon experience overall---achieving your first fully evolved three-stage Pokemon is a great feeling. Raticate introduces the fact that not all Pokemon are capable of evolving twice---some can only evolve once. Now, Pokemon who evolve only once aren't necessarily weaker, but tend to be roughly in-between the strength of the middle-level stages and final-level stages of the families who appear around the same time they do, in Raticate's case, it is somewhat stronger than Pidgeotto in terms of base stats, but doesn't quite measure up to Pidgeot. Rattata evolves slower than Pidgeotto as a way to balance this out as well.
New players might wonder if Raticate can evolve further, but I think Game Freak did a decent job on telegraphing the fact that it's a final form---the middle-form Pokemon encountered so far, such as Ivysaur, Wartortle, Charmeleon, and Pidgeotto, have rather incremental changes from their first forms, leaving plenty of room to develop further. Raticate, on the other hand, has a much more dramatic change, going from a quadruped to a biped and undergoing a color change as well. It's a rather humble evolution all things considered, but compared to the early game Pokemon it's a quite a change, and such a large change gives the impression that this is the peak of evolution for it. The player can't imagine it undergoing such a dramatic evolution once more. Now, Caterpie and Weedle also change quite a bit when they evolve, but in that case they're mimicking the life-cycle of bugs who often undergo a rather notable metamorphosis, and the player will naturally except a cocoon Pokemon to evolve once more. Most 2-Stage Pokemon tend to follow this idea of a rather "big" leap from first-form to second-form to give a sense of conclusion, but of course there are plenty who undergo rather simplistic changes as well. There's no real way to know if a Pokemon is a three-stage or two-stage Pokemon when they first encounter a Pokemon belonging to a family they've yet to see, but often can figure it out thanks to in-game trainers using Pokemon, and utilizing the Dex to see if there's a space for an evolution.
Raticate appears to be based off of a muskrat, but also has elements of the "coypu" (also known as the Nutria) such as having webbed hind feet like the coypu does. Me, well, I always just saw it as a really big rat. Even though you might not think this upon seeing it, like its inspirations, Raticate is described as being a rather skilled swimmer, but this element doesn't really translate into the game as the only Water-type move it possesses, at least in Generation VI, is Rain Dance. Its other features are its long tail, that's a more traditional rat tail compared to the cute tail Rattata had (and probably meant to be slippery and better for underwater movement), its whiskers used for balance, and of course its huge teeth which it uses to perform the many "fang" moves. Raticate may not be that powerful overall, but as an early game Pokemon it can be pretty lethal thanks to its decent attack and speed, and possessing a decent range of rather damaging moves compared to most Pokemon around that time. Like Pidgeot, some of the later Regional Rodent Pokemon outclass it a bit, but I think Raticate is still considered pretty decent among them.
Unlike Rattata, Raticate really hasn't gained any memetic popularity and remains a rather average Pokemon whose only saving grace from obscurity is being one of the original 151. In the television show, Raticate's key moment was being traded for Butterfree, only for Ash to realize how mind-bendingly stupid that was and quickly traded him back. Rocket Rivals Butch and Cassidy also used a Raticate and it was set up as a foil to Meowth as their personal mascot (although unlike Meowth, who was a free Pokemon, Raticate was specifically owned by Cassidy) but this didn't stick---it only appeared three times, and never did much. But hey, it couldn't talk, so it was already falling behind Meowth.
So...the classic Regional Bird, and one of the Regional Bugs, recently got a Mega Evolution...could there be a Mega in Raticate's future as well?