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(Japanese: 姿なき攻撃者 Shapeless Attacker) is the 268th round of the Pokémon Adventures manga.
In Pallet Town, a group of children try and capture a wild Nidorino. One boy throws a Poké Ball at the Nidorino, but it easily knocks the ball away. When the boy groans in frustration, another person approaches him and tells the boy that he should use the Gengar he has to battle it. The boy complies with the person and sends out his Gengar to battle the Nidorino and succeeds in facing it. The person who helped the boy is revealed to be Red, who had returned to Pallet Town with Blue.
As Red and Blue walk to Professor Oak's lab, they comment about how Pallet Town hasn't changed since they were last there. Upon entering the lab, Red and Blue notice that it is empty. They notice three devices with letters addressed to them and Green placed next to them. Upon checking the letters, they notice that the text on them mentions Vermilion City.
Before they can open the letters, Red and Blue hear a commotion outside. They check what's happening, only to find an invisible opponent is attacking their Pokémon. They try and find out what's attacking them, but the enemy is too fast for the Pokédex to scan. Red and Blue have their Pokémon attack the opponent, but it dodges the moves and flies off to escape.
Red decides that if Professor Oak is not there to meet them, then there must be a reason why he is not at the lab. Red prepares to go and find Professor Oak, but Blue decides to check out the Fame Checker that was included with the letters. Upon activating the Fame Checker, a recording of Professor Oak plays. Much to Red and Blue's shock, the recording reveals that Professor Oak intends to take the Pokédex away from them.