Seriously who needs to do more than 100,000 damage per hit? (Unless you're in PVP lol)
If you're trying to aim for high numbers that's more of a personal accomplishment rather than feasible to use since NO trainable monster in game has that much HP.
And that's exactly why I like lions, fast, good damage for training.
We don't over expend our resources on massive damage but can kill very quickly due to our FAST cool down times.