Special Defense is a stat in the Pokemon games that concerns a Pokemon's ability to take less damage from special attacking moves. Ever since the franchise's physical-special split in Generation IV, the stat doesn't just help with certain types; it solely depends on a Pokemon's Special Attack and moves.
Speaking of which, how do the individual types fare in that regard? The type charts are not totally balanced, so you may end up with types that happen to be better in certain stats than others. This list might show some patterns regarding stats and types, as it lists down the Pokemon with the best Special Defense per type.
Note: Mega Evolutions won't be considered for ranking purposes, but they will be examined. Arceus holding a type plate is ineligible.
18 Electric: The Rotom Appliances
Rotom Frost, Mow, Wash, Heat, and Fan all have the same base stats, and from those base stats you get a Special Defense stat of 107, which is far and away the worst on this list.
Even when taking Mega Evolutions into account, it isn't much better, with Mega Ampharos taking it at just 110. The only two other Pokemon that even have 100 are Zekrom and Raikou.
17 Ground: Claydol
The Ground-type isn't much better, also only having four Pokemon reach the 100 mark when including Mega Evolutions.
The best among them is Claydol at 120. While that's generally very good, that can't get it any higher than second-to-last place. The remaining three are Mega Swampert (110), Mega Camerupt (105), and Runerigus (105).
16 Grass: Virizion
The Grass-type fares a little better, flaunting a plethora of solid, specially defensive Pokemon. The leader of that pack is the Sword of Justice, Virizion, at 129.
From there, you have a bunch of Pokemon over the 100 checkpoint, with a few Megas along the way. Eldegoss and Mega Venusaur tie for second place (120), followed by Ferrothorn (116), Cradily (107), Rotom-Mow (107), and ties at 105 (Mega Abomasnow, Roserade, Plant Cloak Wormadam) and 100 (eight Pokemon).
15 Dark: Umbreon & Hoopa Unbound
Umbreon and Hoopa Unbound share the spot for the Dark-types, along with Mega Gyarados, at 130 Special Defense each.
Not many other Pokemon really compete with this trio from the Dark-type, but runner-up Galarian Moltres (125) and a couple of Mega Evolutions in Mega Tyranitar (120) and Mega Sableye (115) can certainly hold their own on the specially defensive end.
14 Normal: Blissey
While it's the poster child of massive HP, Blissey also wears the crown for best Special Defense among Normal-types at 135. That, in conjunction with said 255 HP, makes it arguably the best special wall from a competitive standpoint.
Other than that, a solid number of Pokemon from the type carry very good Special Defense stats. The top of that group, aside from Blissey, includes Meloetta (128), Mega Audino (126), Arceus (120), Kecleon (120), Oranguru (110), Regigigas (110), and Snorlax (110).
13 Ghost: Aegislash
It's a very close race for the top spot of the Ghost-type entry, with five Pokemon in the 130-140 range. Only one Pokemon does reach the higher end of the spectrum though, that being Aegislash in its Shield Forme at 140 on the money.
The other four are Dusknoir (135) and Dusclops (130), Hoopa Confined (130), and Cursola (130). Many more surpass 100, including quite a few Legendaries like Dawn Wings Necrozma (127), Giratina (120 in Altered Forme, 100 in Origin Forme), Lunala (107), and Shadow Rider Calyrex (100).
12 Poison: Toxapex
Toxapex is just an all-around great wall, on both ends. While its physical Defense is better at an astounding 152, its Special Defense is almost as great at 142. With its access to recovery and everything, it's one of the best walls to use competitively.
When comparing it to other Pokemon of its primary Poison-type, there are just a few other standouts, with Nihilego (131) and Dragalge (123) making a pretty good top three. Otherwise, when looking at the rest of the pool, the Poison-type is somewhat middle-of-the-road in that regard.
11 Water: Toxapex
While Toxapex also gets the official crown here for the Water-type, it wouldn't have if Mega Evolutions and, specifically, Primal Reversions were considered. Primal Kyogre actually has a better Special Defense stat at 160.
The roster of specially defensive Water-types is also quite formidable, with a few more Legendaries getting some shine, as well as a few other names of all shapes and sizes, namely regular Kyogre and Mantine (140), Tapu Fini, Araquanid, and Pyukumuku (130), Milotic (125), and Palkia (120).
10 Fighting: Crowned Zamazenta
Crowned Zamazenta (145) and the aforementioned Virizion (129) are the top two among Fighting-types in the Special Defense department.
The bronze medal is split between three Pokemon at 115: Gallade (both regular and Mega), Scrafty, and regular Zamazenta. The three Hitmon's (Hitmonlee, Hitmonchan, Hitmontop) tie at 110, followed by Kommo-o (105) and two more Megas: Mega Heracross (105) and Mega Mewtwo X (100).
9 Dragon: Goodra
The first Pokemon to reach the 150 checkpoint not only has the best Special Defense among Dragon-types, but pseudo-Legendaries as well. When you're talking Mega Evolutions, Goodra ties with Mega Latias in that regard.
Those two contend with a bunch of very good Pokemon for the top spot. Regular Latias takes the silver medal at 130, and Dragalge gets bronze at 123. Then, Mega Latios, Palkia, Giratina, and Reshiram tie at 120. Even Goodra's pre-evolution, Sliggoo, comes in at 113.
8 Steel: Registeel & Probopass
The aforementioned Crowned Zamazenta (145) comes in at a very tightly contested second place among others of its Steel-typing. The first place goes to two Pokemon right at the 150 summit: Registeel and Probopass.
Another old friend, Aegislash, comes in third (140), and then Bastiodon comes in fourth (138). From there, it's a bit of a drop-off to 116 with Ferrothorn and Bronzong, then 115 with two Fairy-types, Crowned Zacian and Magearna.
7 Fire: Ho-Oh
Ho-Oh takes this spot for the Fire-type with 154 points, and no one can even hold a candle to it. The next best is just 120, from another boxart Legendary in Reshiram.
The remaining Fire-type Pokemon are much closer to 100 than 150, with Mega Charizard Y (115), Flareon (110), Rotom Heat (107), and Heatran (106) being the next best options. That's not to say they're terrible at Special Defense or anything, but it's astounding how easily Ho-Oh runs away with this one.
6 Fairy: Florges
There are many more Pokemon as formidable as Ho-Oh from a Special Defense stat perspective. In fact, the type's representative here, Florges, ties with Ho-Oh on the dot at 154 in Special Defense.
Compared to the Fire-type's two Pokemon at 120 and above, the Fairy-type has six, and eight when including Megas. Aside from Florges, that list consists of Carbink (150), Diancie (150), Mega Gardevoir (135), Tapu Fini (130), Sylveon (130), Mega Audino (126), Alcremie (121), and Kantonian Mr. Mime (120).
5 Flying: Ho-Oh & Lugia
While the 154 Special Defense Ho-Oh gets the first place for its primary Fire-type completely uncontested, it has to share its Flying-type spot with its mascot-mate, Lugia.
From there, you have an excellent roster when it comes to Special Defense, though the second place goes to an unexpected contender: Mantine at 140. The rest of the tip of the iceberg is made up of very powerful Pokemon like Kantonian Articuno (125), Galarian Moltres (125), Mantine's pre-evolution, Mantyke (120), Mega Charizard Y (115), and Togekiss (115).
4 Psychic: Deoxys-Defense
Lugia (154) comes pretty close to taking the spot here, but it'll have to settle for second as Deoxys-Defense just edges it out (160). That's quite a feat, as the Psychic-type might just be the best in terms of having the most Pokemon with massive Special Defense.
The roster speaks for itself; a whopping sixteen more Pokemon forms surpass the 120 mark, and nine more surpass 130. Mega Latias (150), Mega Gardevoir (135), and Cosmoem (131) make up the rest of a great top five.
3 Ice: Regice
Regice is the first Pokemon here to reach the 200-point milestone and has — spoiler alert — the second-highest Special Defense ever.
Among Ice-types, no other Pokemon can even touch this Legendary titan. Still, the Ice-type pool isn't necessarily something to scoff at; Cryogonal (135), Ice Rider Calyrex (130), Articuno (125), and Glastrier (110) make a top five that's fairly distant from other Ice-types in this department.
2 Bug: Shuckle
Yes, Shuckle has 230 in both Defense and Special Defense, making it the best ever in both categories. This is either supremely stupid or a fantastic troll from Game Freak.
Regardless, Shuckle is the blowout winner among Bug-types, with the next best Pokemon, Araquanid, having almost 100 less Special Defense (132). After third placer Orbeetle (120), the roster peters out to represent Pokemon with solid, but not spectacular Special Defense stats.
1 Rock: Shuckle
It's kind of the same story for Shuckle's second type, Rock. The next best contenders for the Rock-type are Carbink, Diancie, and Steel-type entry Probopass, who have just 150 Special Defense each.
Bastiodon (138), Nihilego (131), and Mega Tyranitar (120) are the only truly great ones left, with a few more in the 100 to 110 range.