Freezie

A Freezie (originally known as a Slipice) is an enemy made entirely of ice that first appeared in the arcade game Mario Bros. They vary greatly in size and shape, but are instantly recognizable thanks to their permanently puzzled expression. Occasionally, Freezies are used as items to (obviously) freeze enemies. Despite being one of Mario's first enemies, they have only recently started appearing in games again.

Mario Bros.
In the original Mario Bros., Freezies emerge from pipes and travel along the stages' platforms (just like other enemies). They first appear in Stage Nine. When a Freezie reaches the center of a platform, it will coat the entire platform with ice, destroying itself in the process. A frozen platform is very slippery, and it may occasionally drop harmful icicles. Thus, it is in Mario and Luigi's best interest to eliminate these enemies quickly, before they can freeze a platform. Hit a Freezie from below to destroy it and earn five hundred points. Freezies don't count as regular enemies, meaning Mario and Luigi don't have to clear them from the stage to complete the level. If Mario or Luigi touch a Freezie, they will lose a life, but the Freezie will only reverse direction.

Freezie is the only recurring enemy from Mario Bros. that has kept its NES name rather than its original Arcade name.

Super Smash Bros.
The first game outside of the various Mario Bros. remakes to feature Freezie. They are used as items in both Super Smash Bros. Melee and Super Smash Bros. Brawl, randomly appearing on the stage. When a Freezie appears, it will slide across the stage until picked up by a character, falling off the stage, or broken. Freezies in Melee break after a single attack is used on them, provided the attack does damage, while the ones in Brawl are a bit more resilient. Upon being picked up, the Freezie can then be thrown at an opponent, encasing the opponent in a block of ice. While frozen, the opponent will be defenseless for a few seconds, allowing other characters to mercilessly attack the incapacitated foe. The larger the opponent's damage, the longer they will be trapped. If an opponent is knocked-out by a thrown Freezie in Melee, the player receives a "Freezie KO" Bonus. Additionally, the Freezie appears as a collectible trophy.

Mario Kart: Double Dash!!
Freezies also appear in Mario Kart: Double Dash!!. Large, stationary Freezies are located on the ice lake at the end of the racetrack Sherbet Land. If a character drives into a Freezie, their kart will become frozen in a block of ice for a few seconds. After being hit (by kart or item), a Freezie will slide along the ground until it hits a wall and shatters. However, a sliding Freezie can still freeze any karts that it runs into.

Mario Party 6
At Snowflake Lake in this game, Freezies appear during the night blocking players from other paths.

Mario Pinball Land
In this game, a Freezie appears in the Snowy stage. On the second screen of this stage, a Freezie can be found sitting in the middle of the screen while penguins walk around it. Mario must hit this Freezie, pushing the ice creature over a crack in the ice. This then creates a hole that leads to the boss area.

Mario Power Tennis
Freezies appear as a rare obstacle in Mario Power Tennis. On the Mario Bros. Classic stage, the original sprites for enemies are used (instead of modern sprites). When playing a Gimmick Match, Freezies will occasionally slide onto the court and freeze half of a characters play area. Hit the POW Block to stop it.

Dance Dance Revolution: Mario Mix
Additionally, Freezies make an appearance in Dance Dance Revolution: Mario Mix. In the game, a gigantic Freezie is the boss of World Four and the keeper of the fourth Music Key. In fact, the key is lodged in the huge ice creature. This giant Freezie resides on the top of a snow-capped mountain and is surrounded by normal (and much smaller) Freezies. When Mario (or Luigi) and Toad arrive to retrieve the key, Toad politely asks the giant Freezie to return the musical item. However, the Freezie does not respond. As such, Toad tells Mario to melt the giant icicle with his burning hot dance moves. As Mario starts dancing, the giant Freezie (who recognizes the seriousness of the word melt) attempts to block Mario's dance steps with ice. However, the dancing master Mario counters by activating Fire Flowers to keep his hot beat alive. Eventually, the giant Freezie melts away into a puddle of water and Mario recovers the last Music Key.

Mario Hoops 3 on 3
In the game, the Freezies only appeared in the Sherbet Land stage. Mario or any character could grab this item and throw it at opponents. The opponent would be frozen for a short time after being hit.

Mario Super Sluggers
Freezies will appear as stage hazards in Peach Ice Garden, sliding around on the ice. One is also seen crashing into a Toad in the games intro.