Smog

is the OoA: of the OoA: in.

Characteristics
OoA: appears as a gaseous, horned face that challenges OoA: to a deadly game, which plays out over four rounds that combine traditional combat with puzzle-solving elements. Each round begins with an arrangement of solid blocks appearing in the room, and OoA: dividing itself into several smaller forms. These pieces of OoA: attach themselves to the solid blocks and move around their perimeters like NaN Sparks, immune to harm from any of OoA:'s weapons; instead OoA: must use the OoA: to create new blocks that divert the pieces' paths, forcing them to collide and recombine into the original OoA:. To aid in redirecting the pieces, some of the existing blocks can be pushed once, and the pieces can be momentarily slowed down by striking them with the OoA:. If OoA:'s use of the OoA: causes any of the pieces to detach from the blocks, they will vanish and reappear in their original positions. At any point, OoA: can step on a OoA: in the northwest corner of the room to reset the blocks and the pieces of OoA: to their original positions.

In the first and third rounds, OoA: divides into two pieces, while in the second and fourth rounds, it divides into three. Recombining two of the three pieces forms a slower-moving, medium-sized OoA: which must then be combined with the third piece. The small and medium pieces of OoA: will periodically spit blue fireballs toward OoA:, which can be dispelled with the OoA:. When OoA: is returned to its original form, it will detach from the solid blocks and slowly float in pursuit of OoA:, spitting lightning bolts that electrocute OoA: on contact. OoA: is otherwise vulnerable to OoA:'s OoA: in this form and will be defeated by several strikes, setting up the next and more difficult round. After defeating OoA: in the fourth round, it will leave behind a OoA:, and the door to the OoA: will be opened.