Hola,
Creo que te refieres a esto, si es así lo explica al principio del libro:
"Each power has an icon that indicates what type of attack it is:
melee (M), ranged (R), close (C), or area (A).
Basic Attack: The first attack presented is always the monster’s
basic attack (usually a melee attack). Some monsters
have several basic attacks. A basic attack has a circle around its
icon: melee basic attackm or ranged basic attackr.
Monsters use their basic attacks when making opportunity
attacks or when using powers that allow a basic attack."
Es decir, el icono te indica si es un poder de cuerpo a cuerpo, a distancia, area y area limitada.