Magic Rocks are pretty tough cookies at the start of their fights. They come pre-set with Shield, Barrier, Magic Attack Up, and Magic Defense Up attributes. Thankfully, these effects can be nullified by taking out the Magic Pebbles that come alongside the Magic Rocks. The one to the left of it controls the Shield, and Magic Defense attributes while the one on the right controls the Barrier and Magic Attack attributes. Try to take out the one on the left first, and hit this guy with a Wind spell for a quick defeat, because his magic attacks hit pretty hard. If it comes along with a third Magic Pebble, it will have a counter-attack as well. So don't hit it with physical attacks while that pebble is around.