Armos Knights

The Armos Knights (デグアモス, Degu Amos) guard the Pendant of Courage within the Eastern Palace, the first dungeon of A Link to the Past. They can be defeated by sword slashes, about five for each Knight. They can also be destroyed much more easily by three arrows for one Knight. Their fighting strategy is jumping around in formations. Once their numbers are diminished, the last one will turn red and attempt to crush Link with hard stomps around the fighting arena. Three arrows will finish him off.

Link is rewarded with the Pendant of Courage and a Heart Container.

Later in the game, they challenge Link to a rematch in Ganon's Tower. They must be defeated one more time to advance to the top of the Tower, where Agahnim awaits. They are defeated in the same manner as before, but Silver Arrows (if you got them) and the Master Sword make this rematch foolhardy on the part of the Knights. (Remember though, this rematch takes place in a room with an ice floor. Make sure your sword strikes and arrow shots are timed well.)