Ice Block

Ice Blocks are frozen versions of regular Blocks in various Mario games.

Super Mario Bros. 3
Super Mario Bros. 3. If a Buster Beetle gets its hands on one, it will throw it at high speeds towards Mario or Luigi. If one of the plumbers picks one up, he can only hold it for a short time before it disappears, very similar to Grab Blocks. When thrown, it can kill enemies in one piece, not having to throw multiple ones at them.

Super Mario World 2: Yoshi's Island
In Super Mario World 2: Yoshi's Island, they serve as slippery obstacles that cannot be picked up, but can be melted by Yoshi's fire breath after eating a Fire Watermelon, Podoboo or, Pyro Guy. Some Ice Blocks hide items. In this game, the blocks simply look like a block of ice.

Super Mario Sunshine
In Super Mario Sunshine, they appear as transparent blocks emanating an icy mist. They can be melted with F.L.U.D.D.

Super Mario 64 DS
In Super Mario 64 DS, they appear in ice themed levels. They could only be melted with Yoshi's firebreath.

Yoshi's Island DS
In Yoshi's Island DS, they retained their role from the original Yoshi's Island, however they could only be melted by Baby Bowser. Zeus Guys could also do that, and even melt some the young king of Koopas couldn't.

New Super Mario Bros. Wii
In New Super Mario Bros. Wii, there are three types of Ice Blocks: Ice Blocks that consist of enemies frozen by a Ice Flower, blocks that can be picked up and thrown at enemies in World 3 (they can't hurt players, unlike Barrels), and blocks that only appear in World 9-7, which can be melted with fireballs from a Fire Flower or enemy.