Porcupuffer

Porcupuffers (called Porcu-Puffers in Super Mario World) are a species of Cheep-Cheeps that first debuted in Super Mario World. They resemble giant blue-purple Cheep-Cheeps with big red lips and blue spikes all over their back. Their name is a portmanteau of "porcupine" and "puffer fish".

Super Mario World
Porcupuffers appear in Super Mario World, where they follow Mario and Luigi in the water. The Mario Bros. can perform the Spin Jump on them to "ride" them, or use Yoshi. They appear in three levels, the secret level on top of the Vanilla Dome, and a secret area in the Cookie Mountain level. They also appear in a hidden area from Chocolate Island 1.

Super Mario Galaxy
After a long hiatus, this enemy reappears in the game Super Mario Galaxy. However, only one appears, this one being in Drip Drop Galaxy. The Porcupuffer is hidden in an underwater chest.

New Super Mario Bros. Wii
Porcupuffers are featured again in New Super Mario Bros. Wii. Here, they attack exactly the same as the Spike Bass in the predecessor, lying near the surface to pursue the plumber and his party or even leaping from the water to attack. Porcupuffers serve as obstacles for World 4, and they appear again in World 6 in level 6-5 and later in World 9 in level 9-2. They can only be defeated with a fireball, star or koopa shell. They can also be frozen, but they crack out almost instantly, much like a Spiny Cheep-Cheep. In most cases, and not in the obstacle course, Porcupuffers come infinitely, but still one by one, to the player. For example, if a Porcupuffer is defeated by the player, another one will come to take its place several seconds later.

Super Mario Galaxy 2
Porcupuffers reappear is in Super Mario Galaxy 2. Like in the predecessor, they are very rare, and will even disappear a short time after being encountered. They only appear once in Cosmic Cove Galaxy.

Super Mario 3D Land
Porcupuffers later appear in Super Mario 3D Land, inhabiting underwater and beach levels. They retain their appearance from New Super Mario Bros. Wii. In World 6-1, Porcupuffers jump out of waterfalls, attempting to hurt Mario, and may even break some portions of the bridge he uses to reach the end of the level.

New Super Mario Bros. 2
Porcupuffers reappear in New Super Mario Bros. 2, acting the same as they did in New Super Mario Bros. Wii.

New Super Mario Bros. U
Porcupuffers once again appear in New Super Mario Bros. U, behaving the same way as in its predecessors.

Mario and Sonic at the London 2012 Olympic Games
Porcupuffers also appear in Mario and Sonic at the London 2012 Olympic Games. During the Dream Rafting event, the second task a team is required to do is defeat some Porcupuffers. To defeat these Porcupuffers, the participants must Ground Pound the raft at the same time when they're beneath it. They also appear during the Highway Tally game in London Party mode.

Mario & Luigi: Superstar Saga
A similar species called Puffer-Cheeps appear in Mario & Luigi: Superstar Saga.