Stal

Stals, formerly known as Skull Rocks, are skull head enemies with the same appearance as ordinary skulls which Link can pick up and throw. If Link approaches a Stal, it starts to hop toward him, similar to an Armos.

The Legend of Zelda: A Link to the Past
In The Legend of Zelda: A Link to the Past, Skull Rocks appear in the Dark World. Despite their size, Stals can deal a heart of damage to Link. They can be defeated by most weapons, notably the sword. Some Stals hide under grass and are revealed after Link slashes the grass. Link can turn a Skull Rock into a slime by sprinkling Magic Powder on it.

The Legend of Zelda: A Link Between Worlds
In The Legend of Zelda: A Link Between Worlds, Stals appear in Lorule with a similar behavior to before, but noticeably slower. Unlike Armos and Gimos, they face Link as they move.