Johnny's combos generally involve getting his opponent into the air, then juggling them with a combination of P Mist Finer (214P), Turn Up (if a card is already present), Mist Finer Cancels (214[X]D) from 2H and 6H, and Vault~Deal (236H~H).
Once the combo has been extended, S Mist Finer (214S) will provide a HKD to allow for close oki and K Mist Finer will provide an up-to-full-screen knockback effect for a more zoning-focused reward.