After I beat Morty I went into Mahogany Town for some reason (I never did that in the older games) and went up and caught the Red Gyarados. And I used my first Gyarados in the battle. Now I can't decide which to keep. So.About to head into Union Cave:
Lv. 13 Gastly
Lv. 14 Quilava
Lv. 15 Flaffy
Lv. 10 Magikarp
Lv. 6 Onix (Rocky)
Lv. 1 Togepi
Edit: Just beat Bugsy:
Lv. 17 Gastly
Lv. 16 Quilava
Lv. 16 Flaffy
Lv. 15 Togepi