Glass

Glass (commonly referred to as Ice) is light blue in color. Among the three kinds of blocks, this one can be easily broken by all kind of birds. Levels with these blocks are often provided with Blue Birds, as they are very good at breaking these blocks. It is suggested to multiply. the bird in front on the glass block to maintain the greatest strength of the bird. Most birds slow down when they hit glass, but Yellow Bird slows down after only breaking one bit of glass.

Tips

 * Blue Birds are very helpful on destroying glass, especially when "shotgunning"

Trivia

 * Strangely, Yellow Birds are weak against glass, despite glass having a much weaker strength than wood & stone.
 * This possibly applies to stronger birds except for Mighty Eagle, Mighty Dragon, and Space Eagles.
 * Boomerang Birds are also good at destroying glass.
 * Two of Blue's other names, Icepick and Glassjaw, are based on his fondness of ice/glass.
 * Despite the game achieivement referring to ice and the Mattel board game being called "Angry Birds: On Thin Ice," Rovio has confirmed, via Twitter that the material is meant to be glass