Icicle

Icicles are frozen water drops that are present in ice-themed stages in the Mario franchise. They generally act as obstacles that can hurt the player by falling onto them.

Mario Bros.
Icicles first appear during Phase 16 (17 in Japan) of Mario Bros. as obstacles that drop from under the top platforms and pipes, where they would constantly regenerate. They kill the player if they fall upon them; however, icicles can also be deadly if touched while they are still attached to the ceiling. Touching an icicle while it is still a liquid droplet or using the POW Block will prevent it from being formed, though this will not award any points. However, the POW Block will also cause fully formed icicles to drop prematurely.

Most ports do not include icicles. The few that do are the Japan-only PC-8001 port, the Japan-only Kaettekita Mario Bros. on the Famicom Disk System, the Atari 8-bit port, and the Europe-only "Classic Series" port for the NES. They also appear for the Game Boy Advance minigame remake found in the Super Mario Advance series and Mario & Luigi: Superstar Saga.

Mario Clash
In Mario Clash, icicles, known as Ices, behave similarly to the original Mario Bros. game but the upper platforms too high for Mario to touch their droplets. Icicles can be defeated with a Turtle Shell.

Super Mario Bros. Special
In Super Mario Bros. Special, icicles could be defeated by fireballs. They do not regenerate.

Donkey Kong (Game Boy)
Icicles appear in several Iceberg stages of Game Boy Donkey Kong. They audibly shake and then slowly fall down when approached, getting stuck on the floor after they fall. Mario can use its flat end as a platform. After a few seconds, it will shake again and then disappear, soon regenerating in its original location.

In Mario vs. Donkey Kong, falling spikes take the role of icicles, acting very similarly except they are faster and silent.

Super Mario World 2: Yoshi's Island
In Super Mario World 2: Yoshi's Island and Yoshi's Island: Super Mario Advance 3, icicles appear in BLIZZARD!!! and The Very Loooooong Cave as obstacles. Throwing an egg at them would cause them to fall down from the ceiling.

Yoshi's Crafted World
Icicles are also encountered in Yoshi's Crafted World in the level Slip-Slide Isle. They behave like they do in Super Mario Odyssey, in that every icicle that falls becomes a new platform for Yoshi to walk on.

Wario Land 4
In Wario Land 4, icicles appear in 40 Below Fridge and the latter part of Fiery Cavern. They form on the ceiling and fall down, breaking when they hit the ground. Wario usually gets hurt when he touches an icicle, unless he is rolling or frozen. He cannot break icicles himself, but if he rolls or skates through an icicle, it will produce the sound heard when an obstacle is destroyed.

Wario Land: Shake It!
Large icicles appear in Wario Land: Shake It! in the levels Slipshod Slopes and Freezing Fields. When Wario performs an Earthshake Punch nearby, these big icicles fall down and fix into the ground, crushing any enemy underneath. They can also harm Wario as they fall. When wedged in the ground, their top sides can be used as platforms, helping Wario reach high areas. However, they break after a short while, or if Wario pounds or dashes into one, albeit new icicles soon grow back on the piece of ceiling the old ones fell off of. While on the ceiling, an icicle can be destroyed if Wario jumps and hits the tip with his head from underneath, but only while carrying an enemy; jumping into the tip empty-handed does not affect the icicle.

Super Princess Peach
Icicles reappear in Super Princess Peach in many levels of the Gleam Glacier world and behave the same way as they do in Mario Bros.

Super Smash Bros. Brawl
Icicles also make a minor reappearance in Super Smash Bros. Brawl. When fighting on the Ice Climbers' stage, the Summit, they act the exact same way they did in the original Mario Bros., except this time they are indestructible and cannot be melted.

Super Smash Bros. for Wii U
Huge Icicles are featured as stage hazards on the Mushroom Kingdom U stage in Super Smash Bros. for Wii U with their appearance from the New Super Mario Bros. series. They are present in all four variations of the stage. They occasionally fall from the top of the screen and can damage fighters.

Super Smash Bros. Ultimate
Icicles appear in the returning stages Summit from Super Smash Bros. Brawl and Mushroom Kingdom U from Super Smash Bros. for Wii U in Super Smash Bros. Ultimate, retaining their original functions.

New Super Mario Bros. Wii
Icicles make their Super Mario series debut in New Super Mario Bros. Wii. They are found in World 3-3 and. Icicles come long and short, and fall similar to a Thwomp. After falling, they reform after a few seconds. Mario and company, as well as enemies, will take damage if they come in contact with one. There are also some stationary ones that also hurt the player. Icicles can be defeated with a Star or by hitting a block under it as it is falling.

Huge Icicles also make their debut in this game. Unlike normal ones, Huge Icicles will act as platforms after they have fallen, similar to the icicles in Wario Land: Shake It!.

New Super Mario Bros. U / New Super Luigi U / New Super Mario Bros. U Deluxe
Icicles also appear in New Super Mario Bros. U and New Super Luigi U, as well as in New Super Mario Bros. U Deluxe. In New Super Mario Bros. U, they are found in Freezing-Rain Tower and Icicle Caverns, and in New Super Luigi U, they are found in Icicle Tower and Ice-Slide Expressway. Icicles can also be found in World Coin-7. When battling Wendy in all three games, she uses magic to cause icicles to fall onto the player. In Boost Mode, tapping on an icicle in its idle state will cause it to break and never reform, although tapping a falling one will break it but will still eventually reform. Additionally, destroying one of Wendy's icicles with Boost Mode will destroy it but it will then immediately reform.

Super Mario Odyssey
Icicles appear in Super Mario Odyssey, where they are seen in both the Deepest Underground in the Sand Kingdom, and the Icicle Cavern of the Snow Kingdom.

In the Sand Kingdom, they are faceted in shape, and are used by Knucklotec as one of his attacks; Knucklotec will slam his fist into the ground, causing several to fall and embed themselves into the ground. If Knucklotec smashes his fist into a buried icicle, he will briefly writhe in pain, allowing Mario to capture the fist and attack Knucklotec with it. Some of the icicles contain hearts that are released once the icicle is broken.

In the Snow Kingdom, they act similarly to the Huge Icicles in the New Super Mario Bros. games, where they fall and allow Mario to use them as platforms, with a shadow indicating exactly where they will fall.

Super Mario Maker 2
Icicles appear in Super Mario Maker 2, where they function in the same way as they do in the New Super Mario Bros. games. In the editor, they can be placed on ceilings. They can be set to remain stationary, or to drop down when approached by the player, damaging them if they are hit by it. Their stationary form is a darker blue. They can be destroyed if they fall on a player with a Spiny Shell on their head or if the player is sliding. They can also be used as platforms, though falling Icicles fall when stood on.

Mario Kart series
Upward-pointing icicles appear as track obstacles in the Mario Kart 7 and Mario Kart Tour course Rosalina's Ice World. They are scattered throughout the cavern segment of the course. Icicles break upon direct contact with a driver, but will also slow them down. They can otherwise be broken by hitting them with an offensive item such as a shell or a Bob-omb. Icicles are also used to block the player from accessing certain areas in some bonus challenges.

Donkey Kong Country: Tropical Freeze
Icicles can be encountered in Donkey Kong Country: Tropical Freeze in the level Icicle Arsenal. They are remarkably sharp and long, slightly varying in size. They hang from ceilings and drop down when the Kongs walk underneath them. Moments before falling, they signal the player with a slight shake. The Kongs lose one heart from their health meter if they get hit by an icicle; similarly, enemies that are hit by icicles are defeated. After coming down and breaking, icicles yield a single banana.