From the Super Mario Wiki
Spinies (singular Spiny; occasionally pluralized Spinys, as in the Super Mario Adventures comic and Super Paper Mario) are quadrupedal Koopas with a menacing look that first appeared in Super Mario Bros.. They are often thrown by Lakitus in unlimited supplies, but can also be naturally occurring. In Super Mario Bros., the only way the player can defeat them is to shoot a fireball at them, or run into them while being invincible from a Starman.
 Super Mario series
 Super Mario Bros.
In Super Mario Bros., Spinies make their first true appearance when Bowser kidnaps Princess Toadstool; They are always thrown by the Lakitus. These Spinies are only able to be beaten by a Fire Flower or a Starman. If they are hit from below, they will be bumped to the side like a Mushroom, instead of being flipped over, like a Koopa. Most levels that have a Lakitu-and-Spiny combination have many long staightaways with very few places to hide. These levels also usually have one or more very high blocks to jump on the Lakitu, thus stopping the Spinies for a time; though eventually, a new Lakitu will appear. Spinies can also fill some platforms forcing the player to wait for them to move to progress.
 Super Mario Bros.: The Lost Levels
Spinies reappear in Super Mario Bros.: The Lost Levels, playing the same role as in Super Mario Bros..
 Super Mario Bros. 3
Spinies appear under Bowser's rule in Super Mario Bros. 3. Spinies are once again thrown by Lakitus, just like in Super Mario Bros. and can be defeated by Fire Mario, Hammer Mario, and a Starman. Like Buzzy Beetles, Spinies can also hang from the ceiling, dropping down when Mario is close enough and sliding on their shells. Using Raccoon or Tanooki Mario's tail, they can be flipped onto their back and picked up and thrown like a regular Koopa Shell. Unlike Koopa or Buzzy Beetle shells, Mario can not safely jump on a Spiny Shell despite its business end being upside down (however, Mario can do this in the Game Boy Advance remake).
A new sub-species of Spiny is introduced in this game, called the Spiny Egg. It is a Spiny in a green egg that never hatched. It can move around and chase the player until it falls off a cliff or is hit by a Shell, Fireball, Hammer, or Starman. This is the only game that this kind of Spiny Eggs appears in.
In the Japanese version of the remake when the Red Switch e-Reader Card is scanned, all normal-sized Goombas are replaced with Spinies.
Spinies have red faces in this game.
 Super Mario World
When Bowser kidnaps Peach on her vacation to Dinosaur Land, Spinies reappear in Super Mario World. As usual, they are thrown by Lakitus; some of which, called Fishin' Lakitus, hold a 1-Up Mushroom on a fishing pole for the player. Only when Mario or Luigi collects this Mushroom would the Lakitu begin to hurl Spinies at them. The enemies can be defeated by a Fire Flower, Cape, Yoshi, or Starman. Unlike the Koopas in Super Mario World, which hide in their shells after being hit by a Cape, Spinies are instantly defeated, leaving no Shell.
A special silvered colored P-Switch in this game turns all Spinies in a level into Coins for a set amount of time.
In Super Mario All-Stars + Super Mario World a Spiny is one of the eleven characters that appears on the title screen of the game along with Bowser, a Bob-omb, a Goomba, Princess Peach, Mario, Luigi, Toad, Yoshi, a Pidgit and Birdo.
 Super Mario 64 / Super Mario 64 DS
When Bowser takes over Princess Peach's Castle in Super Mario 64 (and in the remake, Super Mario 64 DS), Spinies make another appearance, albeit a rather rare one; they can only be found thrown by a Lakitu in Tiny-Huge Island and Rainbow Ride. When these Spinies are released by a Lakitu, they bounce twice and then start walking around slowly.
This is the only game in which Spinies are nearly impossible to defeat, even with a Shiny Shell or by being lured into the water. In Rainbow Ride, Mario can punch them repeatedly until they fall off the side. However, doing so will not produce any reward, as they will simply fall into a bottomless area. In the remake, Super Mario 64 DS, Spinies can also be defeated by Yoshi, who can eat them and turn them into Eggs. The remake also gives Spinies additional appearances in Goomboss Battle, where they can also be defeated by luring them into the poison gas, and in Sunshine Isles.
 New Super Mario Bros.
Spinies make an appearance in New Super Mario Bros., in which they are treated the same way as in their older side-scrolling games such as Super Mario Bros. or Super Mario Bros. 3. They also have a new ability, however, which is to float in the water by transforming into a Spiny Egg. This ability has yet to appear in another game. Spinies can be defeated by a Fire Flower, a Starman, a Mega Mushroom, or a Blue Koopa Shell. Spinies retained their trick from Super Mario Bros. 3 of dropping from the ceiling when Mario is close. While sliding on their shells, they can be safely stomped on, picked up and thrown since they're upside down. When the "bah" sound is heard in the music, spinies will hop and change direction.
The boss of World 7, Lakithunder throws Spinies after he is jumped on for the first time, making the battle a little more difficult.
 New Super Mario Bros. Wii
Spinies, along with Lakitu, re-appear in New Super Mario Bros. Wii. Spinies can also be frozen via the Penguin Suit and Ice Mario, and, unlike other spiked enemies, they will stay frozen until they break free. Spinies behave in a very similar way to their New Super Mario Bros. appearance. Yoshi can't eat Spinies, but he can grab them with his tongue and spit them out at other enemies, just like Koopa Troopas. Yoshi can also jump on Spinies without getting hurt.
During the Kamek boss fight in World 8, the platforms can occasionally be transformed into Spinies.
While Spinies' undersides cannot be jumped on in the original Super Mario Bros. 3, Mario and the other characters can do this in this game. They can even be used like normal Koopa Troopa shells while upside-down.
 Super Mario Galaxy 2
Despite they did not appear in the prequel, Spinies appear in Super Mario Galaxy 2, mainly in the Yoshi Star Galaxy and the Starshine Beach Galaxy, among others. They are normally seen idly walking around, though when Mario gets near them, they will attempt to hurt Mario by ramming into him. If the player touches a Spiny with Yoshi's tongue, it will turn into a Spiny Egg. The player can then use Yoshi's tongue to grab the Spiny and hold it in Yoshi's mouth, after which Yoshi can spit it back out to attack other enemies.
 Super Mario 3D Land
Spinies return in Super Mario 3D Land, with the same method from Super Mario Galaxy 2. This is the first time in the Mario platformers where Spinies appear to be independently alone, without the presence or the need to be thrown by a Lakitu, as they do not appear in this game.
 New Super Mario Bros. 2
 New Super Mario Bros. U
 Super Mario Bros.: Peach-hime Kyushutsu Dai Sakusen!
Spinies appear in the Mario Japan-only anime movie Super Mario Bros.: Peach-hime Kyushutsu Dai Sakusen!. A Lakitu appears right after Mario, Luigi, and the mysterious dog Kibidango escape from a field of Piranha Plants. This Lakitu starts throwing Spiny Eggs at the trio; the cloud monster misses. The three travelers laugh at the Lakitu for it's poor aim. However, the creature presses a button in its cloud that emits rain and turns the eggs into fully-fledged Spinies. They close in on the group. However, this surrounding does not last long; Mario finds a Magic Vine, which grows and allows Mario and his companions to escape. Before the Lakitu can escape, Mario grabs a piece of its cloud and makes it snow on the Spinies, freezing them. When Mario returns to the earth, the Spiny group was gone.
 Mario Bros.
Although they never actually appear in the original Mario Bros. arcade game, they replace the Shellcreepers in all of the remakes, starting with Super Mario Bros. 3's Battle Mode, and excluding direct ports. The reason for this is so that new players won't try jumping on Shellcreepers, mistaking them for Koopa Troopas.
Spinies infest the pipes in the game, where they can be defeated when the Mario Bros. hit the ground underneath them, flipping them over onto their shell; Spinies can then be touched by Mario or Luigi and sent careening into the water. If they aren't defeated in time, Spinies will flip themselves over and their shell will turn from red to green (and from green to blue if it happens a second time), making it faster. Blue Spinies will also appear when a normal Spiny is the last enemy left on a level.
 DIC cartoons
 The Super Mario Bros. Super Show!
Spinies make a very brief appearance on the The Super Mario Bros. Super Show!, in the episode "Mario and the Red Baron Koopa". King Koopa orders Lakitu to throw several Spiny Eggs down to the people of Pasta Land, which hatch into Spinies, and terrorize the people for a short time. The Spinies seen in this episode were fairly similar to their game appearance. Another Spiny (only one) appears later in the continuation of the show.
 The Adventures of Super Mario Bros. 3
A single Spiny appears in The Adventures of Super Mario Bros. 3 with Lakitu in the episode "Life's Ruff". During a scene, a Lakitu throws a Spiny Egg next to a dog-turned Luigi, which hatched into a Spiny and bit Luigi. This Spiny looked much like the ones seen on The Super Mario Bros. Super Show!.
 Nintendo Adventure Books
 Mario Party series
Spinies also make some appearances in the Mario Party series. The first time they are seen is in Mario Party 3. They appear in Ice Rink Risk, which is a game where players must run around on a very slippery ice rink and avoid Spinie shells, which would disqualify the player by hitting them out of the rink. They later appear in the Mario Party Advance mini-game Dreadmill. Here, only Spiny Eggs appear, and the player must walk past or jump over them so that they don't fall off the treadmill.
They don't appear again until Mario Party 8, where they appear as Spiny Eggs prominently in the mini-game Grabbin' Gold. The goal of this game is to collect as many coins as possible in a basket while avoiding the falling Spiny Eggs. Spiny Eggs also appear in the mini-games Water Ski Spree and Winner or Dinner. Spinies make their re-appearance in Mario Party 9, assisting Lakitu in his boss battle, Sock It to Lakitu. Lakitu throws them at the platform as they either walk right, left, up, or down until they fall off the edge of the platform. They also appear if someone gets them on the blocks that spawn the Bullet Bills.
 Super Smash Bros. series
Spinies appear in Super Smash Bros. Brawl, where Lakitu, as an Assist Trophy, throws them to the ground in their 8-bit form. They walk around and launch players straight into the air. If a character is hit in midair, however, he or she will be thrust directly downward. When the Spinies reach an edge, they fall off.
 Paper Mario series
 Paper Mario
When Huff N. Puff, one of Bowser's henchmen, takes over Flower Fields, Spinies make another appearance, this time in the game Paper Mario. They appear only in Flower Fields and Toad Town Tunnels. The best method to defeat them is to use a POW Block, because that would flip them over and reduce their Defense to 0. A Hammer could also defeat them. One of Mario's partners in Paper Mario, Lakilester, is a Lakitu and can use Spiny Eggs to attack enemies with Spiny Flip and Spiny Surge. These Eggs will not hatch, however.
To attack, Paper Mario Spinies would roll into a ball and charge Mario, causing 4 damage.
 Paper Mario: The Thousand-Year Door
Spinies reappear in Paper Mario: The Thousand-Year Door. Just like in Paper Mario, an effective way of defeating them is to use a Hammer or an item. However, in this game, Spinies are able to curl themselves into a ball and stay there, making them impervious to all attacks. Spinies and a Lakitu are a fighting team in the Glitz Pit, known as Spike Storm. Also, the Dark Lakitus found in the Pit of 100 Trials throw Sky-Blue Spinies; which are merely more powerful Spinies.
 Super Paper Mario
Spinies once again reappear in Super Paper Mario under the control of Count Bleck. They act much like the ones in Super Mario Bros., and are, as usual, thrown by Lakitus. These Spinies may or may not be under Nastasia's Mind Control, like most of Bowser's minions in the game. They appear in the Dotwood Tree, The Overthere and Flipside Pit of 100 Trials; and a new subspecies, the Dark Spiny, appears in the Flopside Pit of 100 Trials. These are more powerful than their relatives, and appear simply as a silhouette. They are not thrown by Lakitus, which is odd for a species of Spiny. They can be defeated the same way all other spiky enemies are.
 Paper Mario: Sticker Star
Spinies reappear in Paper Mario: Sticker Star. Unlike previous Paper Mario games, they more closely resemble their main series' appearance. They only appear in World 1 and 2. If Mario jumps on the Spinies, he takes 5 damage. In one area of Whammino Mountain, they are thrown by a Lakitu. Spinies attack by going into their shell and throwing themselves at Mario.
 Mario & Luigi series
In Mario & Luigi: Superstar Saga, Spinies and Super Flies, stronger versions of the Fighter Flies, infest the sewers of Beanbean Castle. However, instead of their traditional appearance, they have green shells, yellow spikes, and white shell lining, similar to Bowser's shell , rather high defense (at that point in the game). Its main weakness is Luigi's Thunderhand, which is unavailable when the Mario Bros. have to fight them. This means they have to defeat them using their Hammers or the advanced version of Splash Bros.
A subspecies of Spiny, the Sharpea, also appear in this game. They are considered "Beanified" Spinies, with a yellow shell that is molded to their body and green spikes. They were thrown by Lakipeas, which were the "Beanified" versions of Lakitus.
Even though true Spinies never appear in Mario & Luigi: Partners in Time, a subspecies of Spinies appears. This species, the Spiny Shroopa, is the Shroobified version of a Spiny. Lakitufos, which are the Shroobified version of a Lakitu, throws these spinies.
Spinies also appear in Mario & Luigi: Bowser's Inside Story during the Giant Bowser fight against Bowser's Castle. They will come when the castle door opened and position themselves in four groups in front of it, making Bowser unable to punch it. He has to breath fire to harm the castle, which gets rid of them. They are more of an obstacle than an enemy in this game.
 Dance Dance Revolution: Mario Mix
Spinies appear in Dance Dance Revolution: Mario Mix, but the dance game also introduces Ice Spinies. Both the regular Spinies and the Ice version will make the Dance Meter go down when stepped upon. The Ice Spinies, however, are not Spinies at all and are simply a frozen piece of ice with sharp spikes on them. It is unknown why this enemy is named "Spiny."
 Mario Football series
Spinies appear in the Mario Football series as an item: a huge, spinning, spiked shell. This shell will bounce off walls until it eventually hits a player. When it impacts with a character, it will explode, and possibly hit other players as well. If any players are hit, they will be stunned for a few seconds.
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