OK here it is:
1. go to Classroom 1-2 and trade a little girl an EnergBom K chip for a DublShot C Chip
2. go to Aquarium HP and trade a green navi a PnlRetrn * for a Geddon A Chip
3. head to the first room of the Aquarium in front of the piranha tank and there is a boy there who wants to trade his HiBoomer V for your DublShot C
4. head to the WaterMchComp(Water vending machine) and trade a pink navi your HiBoomer V for a GrabRvng I
5. head to Central town and beneath the Airbus station and trade a Barr100 H for an AirHocky M chip
6. go to the AirCndtrComp a girl navi wants to trade you her AirSpin2 L for an AuraHed1 B
7. go inside the Sky Town Cmnd Center and there is a woman there who wants to trade your GrabRvng I for a BigBomb O
8.go to ACDC Comp or Jack into the squirrel and trade a Navi your BigBomb O chip for JustcOne J!!!
I edited from an Ashman kae post, i hope it helps ALL that need the justone.
I don´t use action replay to get *insert rare item, shiny poke, rare chip, etc.* i got it legally and right.
And also
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