It would seem we might have another Haymaker on our hands....
...Without further ado, here's Koga's Ditto (translation from Edo)...

    Koga's Ditto
    Type:  Basic Colorless Pokemon
    LV.12     HP 40
    C:   Might
      Effect:  Flip a coin.  If heads, this Pokemon's maximum HP
        becomes 80.  (Benching this Pokemon ends this effect.)
    C:   Tackle:   10
      Effect:  If this Pokemon is affected by "Might", this attack
        does 30 damage instead.
    -C        Retreat
    F         Weakness
    P         Resistance (Damage -30)
    No. 132 (Rare Hologram)

Okay, this guy is a little chansey, but once affected by "Might,"  this guy
makes a mess of the opponent with 30 damage for 1 colorless energy.  A
resistance to psychic is nice, with all those Promo Mewtwo, and the fighting
weakness isn't that bad, since Hitmonchan is kinda out of the picture.  just
make sure you pack scoop up, since retreating him could likely kill him, and
keep this little guy off the bench, where he is otherwise vulnerable. 
Although he requires a coinflip, prepare to see this guy a lot, he's
colorless and pretty heavy duty.
                                                -FossilMagikarp
                                                Email: Edestus360@aol.com