In the Theravada tradition:

1. There is no self in all phenomena (including the five aggregates).
2. The five aggregates and the rest of nature and the world is always changing and not permanent (anicca).
3. Emptiness is only about the emptiness of self in all phenomena (including the five aggregates). The aggregates and the world definitely exist. These are not empty.
4. Suffering definitely exists (first noble truth).
5. The Theravada practitioner has to strive to become free from suffering. Nibbana exists, and is permanent and unchanging.

Whereas, in the Mahayana tradition:

1. There is no self in all phenomena (including the five aggregates).
2. The five aggregates and the rest of nature and the world is always changing and not permanent (anicca).
3. Emptiness refers to the emptiness of everything ([including Nirvana](https://buddhism.stackexchange.com/a/1956/471)) - the self, the five aggregates, the world, nature etc.
4. According to the [Heart Sutra](http://www.buddhanet.net/e-learning/heartstr.htm), "There is No Truth of Suffering, Of the Cause of Suffering,Of the Cessation of Suffering, Nor of the Path."
5. According to the [Heart Sutra](http://www.buddhanet.net/e-learning/heartstr.htm), "There is No Wisdom, and There is No Attainment Whatsoever."

So, why should the Mahayana practitioner strive for anything at all, if everything is emptiness (nothing really exists), and there is no suffering at all, and there is no wisdom to be gained, and there is nothing at all to attain?