Chi-Ji and Onyxia

Yesterday I had a Deep Breath task for Onyxia and a "deal damage with Blazing Song" for Chi-Ji. So I set up Cookie's target dummies and shot with Chi-Ji on Onyxia. Now the important observation: Deep Breath is supported by the heal power, therefore heals a lot! And next turn you have 30+ fire spell damage. I had to make sure not to one-shot Onyxia with Blazing Song.

Could this work in any PVE or PVP comp? E.g. making some of thr boss fights easier?

This seems incredible hard for pvp, since Onyxia has barely any health, requires a cooldown ability and only pays off a turn later if she does not die before you can use a fire ability.

For PvE almost every wanky combo works, but the slow nature of it basically assures that it won't be the best option, which is fine if you only want to have fun. I would probably pair both of them with either Cornelius as a tank or Ragnaros for more aoe damage with his 3. ability. Oh, and ofcourse cookie in the backline + some other stuff.